| Person | Born / dead | Served on |
| | O'Bernier, Walter Edward, USNR | | | USS Block Island (CVE 21) |
|
| | O'Bonne, Frederick, Merchant Navy | | -1942 | Ilorin + |
| | O'Boyle, T.V., | | | Adinda |
| | O'Brian, J., Merchant Navy | | | La Cordillera |
| | O'Briant, Jr., Henry C., USN | | | Alcoa Pathfinder |
| | O'Brien, Robert Joseph, Merchant Marine | | -1942 | Alcoa Pilgrim + |
| | O'Brien, Timothy, Merchant Marine | | -1943 | Arthur Middleton + |
| | O'Brien, Joseph P., Merchant Marine | | -1942 | East Indian + |
| | O'Brien, Timothy, Merchant Marine | | -1943 | Puerto Rican + |
| | O'Brien, John, Merchant Marine | | -1943 | Henry R. Mallory + |
| | O'Brien, Michael Francis, Merchant Navy | 1903 | -1941 | Eastlea + |
| | O'Brien, Patrick Joseph, RN | 1886 | -1939 | HMS Courageous (50) + |
| | O'Brien, Arthur Edward, RN | 1901 | -1939 | HMS Royal Oak (08) + |
| | O'Brien, Joseph, RN | 1911 | -1941 | HMS Barham (04) + |
| | O'Brien, Albert James, RN | 1919 | -1942 | HMS Eagle (94) + |
| | O'Brien, John, Merchant Navy | 1887 | -1939 | Bowling + |
| | O'Brien, Joe, RN | 1913 | -1940 | HMS Exmouth (H 02) + |
| | O'Brien, Dennis, RN | | -1942 | HMS Martin (G 44) + |
| | O'Brien, Maurice Francis, RN | 1921 | -1940 | HMS Forfar (F 30) + |
| | O'Brien, John, RN | 1920 | -1942 | HMS Leda (J 93) + |
| | O'Brien, Edward Skilly, RM | | -1942 | HMS Fidelity (D 57) + |
| | O'Brien, Thomas Wilton, RN | 1920 | -1943 | HMS Itchen (K 227) + |
| | O'Brien, Michael Pierce, RNVR | 1924 | -1944 | HMS Blackwood (K 313) + |
| | O'Brien, Harold, RN | 1925 | -1944 | HMS Kite (U 87) + |
| | O'Brien, Owen, RN | 1925 | -1944 | HMS Mounsey (K 569) + |
| | O'Brien, Vincent P., USNR | | -1943 | Jeremiah Van Rensselaer + |
| | O'Brien, Clifford Gregory, USNR | | -1945 | USS Frederick C. Davis (DE 136) + |
| | O'Brien, Joseph F., USN | | -1943 | West Portal + |
| | O'Brien, Lawrence, Merchant Navy | 1881 | -1941 | Robert L. Holt + |
| | O'Brien, Kenneth S., Merchant Navy | 1908 | -1940 | Calabria + |
| | O'Brien, George, Merchant Navy | 1903 | -1942 | Irish Pine + |
| | O'Brien, Edmond Robert, RN | 1905 | -1940 | Jamaica Progress + |
| | O'Brien, William Charles, Merchant Navy | 1907 | -1940 | Mill Hill + |
| | O'Brien, Dairmuid Phadrig, Merchant Navy | 1909 | | Frederick S. Fales |
| | O'Brien, Daniel, Merchant Navy | 1887 | -1942 | Baron Ogilvy + |
| | O'Brien, Kelvin Francis, Merchant Navy | 1921 | -1941 | Rose Schiaffino + |
| | O'Brien, John, Merchant Navy | 1918 | -1940 | Samala + |
| | O'Brien, Patrick, Merchant Navy | 1921 | -1940 | Samala + |
| | O'Brien, Michael, Merchant Navy | 1914 | -1940 | Tregenna + |
| | O'Brien, George, Merchant Navy | 1900 | -1939 | Navasota + |
| | O'Brien, Joseph, Merchant Navy | 1897 | -1939 | Navasota + |
| | O'Brien, John, Merchant Navy | 1912 | -1942 | Ocean Crusader + |
| | O'Brien, George, Merchant Navy | 1884 | -1942 | Biela + |
| | O'Brien, Christopher, Merchant Navy | 1923 | -1943 | Empire Lytton + |
| | O'Brien, Daniel, Merchant Navy | | -1943 | Kyleclare + |
| | O'Brien, L., Merchant Navy | | -1943 | Kyleclare + |
| | O'Brien, Richard, Merchant Navy | | -1943 | Kyleclare + |
| | O'Brien, William, Merchant Navy | 1888 | -1940 | Stancliffe + |
| | O'Brien, William, Merchant Navy | 1898 | -1943 | Lancastrian Prince + |
| | O'Brien, John James, RN | | | HMS LST-404 |
| | O'Brien, Arthur William, Merchant Marine | | | Atlantic States |
| | O'Brien, John, RN | | | HMS Courageous (50) |
| | O'Brien, William, RN | | | HMS Courageous (50) |
| | O'Brien, Robert James, USNR | | | USS Blakeley (DD 150) |
| | O'Brien, George Edward, USN | | | USS Gannet (AVP 8) |
| | O'Brien, Thomas Joseph, British Army | 1908 | -1943 | Dafila + |
| | O'Brien, Jr., Emile E., USN | | | USS Fogg (DE 57) |
| | O'Brien, John Francis, USNR | | | USS LST-359 |
| | O'Brien, Clifford, Merchant Navy | | | Leticia |
| | O'Brien, G., Merchant Navy | | | Empire Dew |
| | O'Brien, Charles Patrick, USNR | | | USS Block Island (CVE 21) |
| | O'Brien, Cornelius James, USNR | | | USS Block Island (CVE 21) |
| | O'Brien, James Joseph, USNR | | | USS Block Island (CVE 21) |
| | O'Brien, James Joseph, USNR | | | USS Block Island (CVE 21) |
| | O'Brien, John James, USNR | | | USS LST-348 |
| | O'Brien, Charles, Merchant Navy | | | Merope |
| | O'Brien, Ronald, Merchant Navy | | | Livingston |
| | O'Bryan, Glenn A., US Army | | -1944 | Leopoldville + |
| | O'Bryant, Leroy Melvin, Merchant Marine | | -1944 | Penelope Barker + |
| | O'Byrne, Patrick, NAP | 1914 | -1941 | HMS Ariguani (F 105) + |
| | O'Byrne, Desmond P., RM | | | HMS Royal Oak (08) |
| | O'Callaghan, Desmond, RN | | -1944 | HMS Tweed (K 250) + |
| | O'Callaghan, Michael, Merchant Navy | 1916 | -1942 | Irish Pine + |
| | O'Callaghan, Jeremiah, Merchant Navy | | | Hai Hing |
| | O'Callaghan, Thomas, Merchant Navy | 1900 | -1942 | Edencrag + |
| | O'Callaghan, James, Merchant Navy | 1899 | -1944 | Shirvan + |
| | O'Callaghan, Peter, Merchant Navy | 1899 | -1944 | HMS Salviking + |
| | O'Callaghan, J., Merchant Navy | 1912 | | Arandora Star |
| | O'Carroll, John Lawrence, RN | | -1944 | HMS Mahratta (G 23) + |
| | O'Connell, Eugene, RN | | -1941 | HMS Barham (04) + |
| | O'Connell, Vincent, RN | | -1945 | HMS Vervain (K 190) + |
| | O'Connell, Joseph, Merchant Navy | 1896 | -1942 | Irish Pine + |
| | O'Connell, Watson Edward, Merchant Navy | 1904 | -1941 | Empire Springbuck + |
| | O'Connell, Richard J., Merchant Navy | 1917 | -1940 | Frederick S. Fales + |
| | O'Connell, James, Merchant Navy | 1888 | -1941 | Larpool + |
| | O'Connell, Daniel, Merchant Navy | 1914 | -1942 | Glenlea + |
| | O'Connell, Michael, Merchant Navy | 1916 | -1942 | Glenlea + |
| | O'Connell, Michael Albert, Merchant Navy | 1912 | -1942 | Roxby + |
| | O'Connell, Watson Edward, Merchant Navy | | | Hylton |
| | O'Connell, John, Merchant Navy | 1912 | -1942 | Empire Gem + |
| | O'Connell, George, Merchant Navy | 1903 | -1942 | Traveller + |
| | O'Connell, Thomas Henry, RN | | -1943 | Leadgate + |
| | O'Connell, Howard Ferguson, RCAF | 1919 | -1943 | Amerika + |
| | O'Connell, J., RN | | | HMS Zinnia (K 98) |
| | O'Connell, Robert Emmett, USNR | | | USS Block Island (CVE 21) |
| | O'Connell, John, Merchant Navy | 1915 | -1941 | Niceto de Larrinaga + |
| | O'Conner, Daniel, RN | | -1941 | HMS Picotee (K 63) + |
| | O'Conner, Gerald Wendell, USNR | | | USS Donnell (DE 56) |
| | O'Connor, William A., Merchant Marine | | -1942 | Eastern Sword + |
| | O'Connor, James F., Merchant Marine | | -1942 | Federal + |
| | O'Connor, Joseph Michael, Merchant Marine | | -1942 | Illinois + |
| | O'Connor, Martin F., Merchant Marine | | -1943 | Jonathan Sturges + |
| | O'Connor, Thomas Patrick, RCNR | 1906 | -1943 | HMCS St. Croix (I 81) + |
| | O'Connor, Sidney, RN | 1925 | -1944 | HMS Bickerton (K 466) + |
| | O'Connor, Edward Anthony, RN | 1926 | -1944 | HMS Whitaker (K 580) + |
| | O'Connor, William, RN | 1926 | -1945 | HMS Vervain (K 190) + |
| | O'Connor, Armond, Merchant Navy | | | Leiv Eiriksson |
| | O'Connor, Joseph, Merchant Navy | 1911 | -1942 | Irish Pine + |
| | O'Connor, Thomas, Merchant Navy | | | Andalucia Star |
| | O'Connor, Robert, Merchant Navy | 1923 | -1941 | Darkdale + |
| | O'Connor, John, RN | 1913 | -1942 | Empire Star + |
| | O'Connor, Michael, Merchant Navy | 1894 | -1941 | Hatasu + |
| | O'Connor, Adam, Merchant Navy | 1907 | -1943 | Mary Slessor + |
| | O'Connor, Thomas, Merchant Navy | 1919 | -1942 | Ceramic + |
| | O'Connor, Michael, Merchant Navy | 1923 | -1941 | Oropesa + |
| | O'Connor, Martin, British Army | 1919 | -1942 | San Demetrio + |
| | O'Connor, John, RN | | -1943 | Zeus + |
| | O'Connor, Frank, Merchant Navy | 1926 | -1943 | Melbourne Star + |
| | O'Connor, Herbert, Merchant Navy | 1902 | -1943 | Melbourne Star + |
| | O'Connor, Michael, Merchant Navy | 1916 | -1944 | Janeta + |
| | O'Connor, Cornelius, Merchant Navy | 1885 | | Robert E. Lee |
| | O'Connor, D.J., Merchant Navy | 1921 | | Arandora Star |
| | O'Connor, Michael J., Merchant Navy | 1913 | | Hatarana |
| | O'Connor, Cornelius F., Merchant Marine | 1923 | | M.F. Elliott |
| | O'Connor, C.G., South African Army | 1901 | -1942 | Nova Scotia + |
| | O'Connor, T., | | -1942 | Yorktown + |
| | O'Connor, Terrence Patrick, RCNVR | | | HMCS Valleyfield (K 329) |
| | O'Connor, J., Merchant Navy | | | Empire Dew |
| | O'Connor, Dennis Joseph, USNR | | | USS Block Island (CVE 21) |
| | O'Connor, Daniel E., US Army | | -1943 | Dorchester + |
| | O'Daniel, Herman, Merchant Marine | 1920 | | Cities Service Missouri |
| | O'Dea, Andrew, Merchant Navy | | -1941 | Havtor + |
| | O'Dea, Eric Warri, RN | | -1944 | HMS Kite (U 87) + |
| | O'Dea, Michael, Merchant Navy | 1912 | -1942 | Ocean Crusader + |
| | O'Dell, Paul Frederick, USN | 1908 | -1943 | USS Dorado (SS 248) + |
| | O'Donell, Ervin Leroy, USNR | | | USS Block Island (CVE 21) |
| | O'Donnell, Thomas D., Merchant Marine | | | Charles Pratt |
| | O'Donnell, John H., US Army | | -1944 | Leopoldville + |
| | O'Donnell, William Francis, Merchant Navy | 1910 | -1940 | Upwey Grange + |
| | O'Donnell, Patrick, British Army | 1907 | -1942 | Aldington Court + |
| | O'Donnell, John, Merchant Navy | 1923 | -1941 | Lapwing + |
| | O'Donnell, James, RN | | -1941 | Runa + |
| | O'Donnell, Samuel, Merchant Navy | 1923 | -1940 | Empire Statesman + |
| | O'Donnell, Neil, Merchant Navy | 1913 | -1942 | Nova Scotia + |
| | O'Donnell, Walter, RNPS | 1916 | -1942 | Ceramic + |
| | O'Donnell, James, Merchant Navy | 1914 | -1943 | Empire Whale + |
| | O'Donnell, John, Merchant Navy | 1919 | -1943 | Kanbe + |
| | O'Donnell, Harry Smith, USNR | | | USS Gannet (AVP 8) |
| | O'Donnell, Matthew Augustine, USNR | | | USS Fogg (DE 57) |
| | O'Donnell, Ignatius Peter, USN | | -1942 | USS Atik (AK 101) + |
| | O'Donnell, John Patrick, USN | | -1942 | USS Atik (AK 101) + |
| | O'Donnell, John J., US Army | | -1943 | Dorchester + |
| | O'Donoghue, Timothy J., Merchant Marine | | -1942 | Topa Topa + |
| | O'Donoghue, Thomas, Merchant Navy | 1922 | -1942 | Irish Pine + |
| | O'Donoghue, Basil David, RANVR | 1914 | -1942 | Ceramic + |
| | O'Donovan, William Patrick, Merchant Marine | | -1942 | Joseph M. Cudahy + |
| | O'Donovan, Cornelius, RN | 1914 | -1941 | HMS Stanley (I 73) + |
| | O'Donovan, Arthur James, Merchant Navy | 1921 | -1940 | Kayeson + |
| | O'Donovan, Jeremiah David Joseph, Merchant Navy | 1913 | -1941 | Hindpool + |
| | O'Donovan, John, Merchant Navy | 1911 | -1945 | Oriskany + |
| | O'Dowd, Walter, Merchant Navy | 1909 | -1941 | Umona + |
| | O'Dowd, John, Merchant Navy | 1889 | | British Colony |
| | O'Driscoll, William, Merchant Navy | 1900 | -1943 | Lorient + |
| | O'Driscoll, Flurance, Merchant Navy | 1926 | -1943 | Clarissa Radcliffe + |
| | O'Driscoll, Michael, Merchant Navy | 1920 | | Lochkatrine |
| | O'Flynn, Michael, Merchant Navy | 1912 | -1942 | Irish Pine + |
| | O'Ghany, Solomon, Merchant Navy | | | Frank Seamans |
| | O'Gorman, Michael Bernard, RCNVR | 1921 | -1944 | HMCS Shawinigan (K 136) + |
| | O'Gorman, Theodore Arthur, USNR | | | USS Fechteler (DE 157) |
| | O'Grady, John Joseph, RN | | -1942 | HMS Firedrake (H 79) + |
| | O'Grady, John William, USCGR | | -1944 | USS Leopold (DE 319) + |
| | O'Grady, John, Merchant Navy | 1912 | -1941 | Linaria + |
| | O'Grady, Daniel George, RCNVR | | | HMCS Valleyfield (K 329) |
| | O'Hagan, Patrick H., Merchant Marine | | -1942 | Velma Lykes + |
| | O'Hagan, Bernard Rankin, RN | | -1942 | HMS Edinburgh (16) + |
| | O'Hagan, Jack Michael, RN | 1925 | -1944 | HMS Penelope (97) + |
| | O'Hagan, Michael, NAP | 1903 | -1940 | HMS Forfar (F 30) + |
| | O'Hagan, John, Merchant Navy | 1891 | -1942 | Aldington Court + |
| | O'Hagan, Charles Alex, Merchant Navy | 1876 | -1942 | Nova Scotia + |
| | O'Hagen, Andrew T., Merchant Navy | 1921 | | Peru |
| | O'Hair, Edward Ernest Peacock, RN | | -1940 | HMS Spearfish (N 69) + |
| | O'Halloran, B.S., RNZAF | | | Waiwera |
| | O'Handley, John Alexander, Merchant Marine | 1919 | | Alcoa Pathfinder |
| | O'Hanley, Albert, Merchant Navy | 1916 | -1941 | Maplecourt + |
| | O'Hanley, Earl, Merchant Navy | 1910 | -1941 | Maplecourt + |
| | O'Hanlon, Thomas, NAP | 1923 | -1940 | HMS Forfar (F 30) + |
| | O'Hanlon, Patrick Joseph, Merchant Navy | 1897 | -1942 | Vimeira + |
| | O'Hanlon, Michael, Merchant Navy | | | Andalucia Star |
| | O'Hanlon, Charles, Merchant Navy | 1905 | -1942 | Nova Scotia + |
| | O'Hanlon, James, Merchant Marine | | | M.F. Elliott |
| | O'Hanlon, Martin Stanislans, Merchant Navy | | | Alexia |
| | O'Hara, Patrick, Merchant Navy | 1924 | -1943 | Christian Michelsen + |
| | O'Hara, Robert, RNR | | -1941 | HMS Cossack (G 03) + |
| | O'Hara, William R.M., USNR | | -1943 | Samuel Heintzelman + |
| | O'Hara, James, Merchant Navy | 1911 | -1942 | Winamac + |
| | O'Hara, Emeil Cyril, Merchant Navy | 1912 | -1941 | Baltallinn + |
| | O'Hara, James, Merchant Navy | 1890 | -1940 | Matina + |
| | O'Hara, George Christopher, Merchant Navy | 1921 | -1941 | Dione II + |
| | O'Hara, A., Merchant Navy | 1913 | | Arandora Star |
| | O'Hara, Earl, Merchant Navy | 1916 | | Høegh Giant, Robert E. Lee |
| | O'Hara, James, Merchant Navy | | | Irish Oak |
| | O'Hara, William, Merchant Navy | 1886 | | Adda |
| | O'Hare, John, RN | 1913 | -1943 | HMS P-615 + |
| | O'Hare, Edward, Merchant Navy | 1900 | -1942 | Laconia + |
| | O'Hare, Joseph Vincent, Merchant Navy | 1918 | -1940 | Har Zion + |
| | O'Hare, Henry, Merchant Navy | 1919 | -1942 | Ceramic + |
| | O'Hare, Henry, Merchant Navy | 1912 | | Kupa |
| | O'Haus, Peter, USNR | | -1943 | USS Bristol (DD 453) + |
| | O'Hea, Dr. Matthew A., Civilian | 1920 | -1943 | Vaalaren + |
| | O'Kane, James Francis, Merchant Navy | 1922 | -1942 | Empire Spenser + |
| | O'Kane, John Andrew, Merchant Navy | 1924 | -1941 | Medjerda + |
| | O'Kane, Edward, Merchant Navy | 1916 | -1942 | Dayrose + |
| | O'Kane, J., Merchant Navy | | | Tafna |
| | O'Kane, James, Merchant Navy | | | Penolver |
| | O'Kane, James, Merchant Navy | 1923 | | British Mariner |
| | O'Kane, Th., USN | | | Suriname |
| | O'Keefe, Cornelius, RN | | | HMS Aurania (F 28) |
| | O'Keefe, Joseph, USNR | | -1943 | Jeremiah Van Rensselaer + |
| | O'Keefe, Patrick, Merchant Navy | 1922 | -1942 | Lifland + |
| | O'Keefe, Donald, USNR | | | USS Barr (DE 576) |
| | O'Keefe, Harry Elliott, USNR | | | USS Block Island (CVE 21) |
| | O'Keefe, Wilbur Fiske, USNR | | | USS Block Island (CVE 21) |
| | O'Keefe, Nicholas John, Merchant Marine | 1924 | -1969 | Irénée Du Pont |
| | O'Keeffe, Raymond Stephen, FAA | 1919 | -1941 | Aguila + |
| | O'Keeffe, Maurice Brian, Merchant Navy | 1923 | -1941 | Nottingham + |
| | O'Keeffe, Cyril George, Merchant Navy | 1900 | -1941 | Bassano + |
| | O'Keeffe, Francis, British Army | | -1941 | Shuntien + |
| | O'Keeffe, Daniel J., Merchant Marine | | | Dorchester |
| | O'Kora, Frederick, British Army | | -1942 | Maritima + |
| | O'Leary, Jeremiah D., Merchant Marine | | -1943 | Robert Gray + |
| | O'Leary, Timothy, RN | 1895 | -1941 | HMS Galatea (71) + |
| | O'Leary, Michael, Merchant Navy | 1902 | -1940 | Pearlmoor + |
| | O'Leary, Thomas, Merchant Navy | 1918 | -1941 | Lissa + |
| | O'Leary, Jeremiah, Merchant Navy | 1889 | -1939 | Deptford + |
| | O'Leary, John, Merchant Navy | 1879 | -1942 | Beaverdale |
| | O'Leary, J., Merchant Navy | 1920 | | Empire Sailor |
| | O'Leary, James D.F., RN | | | HMS Royal Oak (08) |
| | O'Ligny, Arthur Hubert, Merchant Marine | | -1943 | Yorkmar + |
| | O'Loughlin, Louis James, RN | 1913 | -1942 | HMS Firedrake (H 79) + |
| | O'Loughlin, Dennis, Merchant Navy | 1925 | -1942 | Boston + |
| | O'Loughlin, George Albert, Merchant Navy | 1891 | -1952 | Accra |
| | O'Mahony, Edmund, RN | | -1942 | HMS Eagle (94) + |
| | O'Mahony, A.J., Merchant Navy | | | Irish Oak |
| | O'Malley, Owen, RN | 1900 | -1942 | HMS Matabele (G 26) + |
| | O'Malley, John O., USNR | | | USS LST-333 |
| | O'May, Hugh Harper, Merchant Navy | 1908 | | Waroonga |
| | O'Meara, James, Merchant Navy | 1921 | -1941 | Beaverdale + |
| | O'Meara, Michael Joseph, British Army | 1919 | -1942 | Garlinge + |
| | O'Neal, Don, Merchant Marine | 1925 | -1944 | Jacksonville + |
| | O'Neal, Clifford, Merchant Navy | | -1942 | Empire Explorer + |
| | O'Neal, Dallas E., USCG | | | USCGC Alexander Hamilton (WPG 34) |
| | O'Neil, Henry, RN | | -1942 | HMS Martin (G 44) + |
| | O'Neil, Lionel Henry, Merchant Navy | 1912 | -1941 | Avoceta + |
| | O'Neil, John, Merchant Navy | 1913 | -1941 | Jedmoor + |
| | O'Neil, Thomas, Merchant Navy | 1892 | -1940 | Manchester Brigade + |
| | O'Neil, John, Merchant Navy | 1903 | | Robert E. Lee |
| | O'Neil, John, Merchant Navy | | | Empire Drum |
| | O'Neil, B., Merchant Marine | | | Beatrice |
| | O'Neil, James L., Merchant Marine | 1898 | | Robin Moor |
| | O'Neil, Jr., William Joseph, USNR | | | USS Block Island (CVE 21) |
| | O'Neill, William, RN | 1908 | -1941 | HMS Barham (04) + |
| | O'Neill, Dennis Stephen, RN | 1919 | -1941 | HMS Galatea (71) + |
| | O'Neill, John Shiels, RNVR | 1914 | -1944 | HMS Penelope (97) + |
| | O'Neill, Joseph, RN | 1921 | -1941 | HMS Stanley (I 73) + |
| | O'Neill, Edward Francis, RN | 1913 | -1944 | HMS Bullen (K 469) + |
| | O'Neill, Grant P., US Army | | -1944 | Leopoldville + |
| | O'Neill, Cornelius Edward, USN | | -1943 | USS Buck (DD 420) + |
| | O'Neill, Andrew, Merchant Navy | 1922 | -1941 | Robert L. Holt + |
| | O'Neill, Henry, Merchant Navy | 1924 | -1942 | San Gerardo + |
| | O'Neill, Denis Alfred, RN | 1918 | -1942 | Empire Mica + |
| | O'Neill, Francis Roy, RAAF | 1916 | -1942 | Yngaren + |
| | O'Neill, Matthew, Merchant Navy | 1901 | -1942 | Irish Pine + |
| | O'Neill, J., Merchant Navy | 1912 | -1942 | Abosso + |
| | O'Neill, Charles, RN | 1922 | -1942 | Athelsultan + |
| | O'Neill, John, Merchant Navy | 1918 | -1939 | Stanholme + |
| | O'Neill, Daniel, Merchant Navy | 1920 | -1940 | British Premier + |
| | O'Neill, Patrick, RN | 1921 | -1942 | Empire Sky + |
| | O'Neill, John Patrick, Merchant Navy | 1898 | -1942 | Lindenhall + |
| | O'Neill, Michael Joseph, Merchant Navy | 1916 | -1941 | Edwy R. Brown + |
| | O'Neill, P., Merchant Navy | | -1943 | Kyleclare + |
| | O'Neill, Terence, Merchant Navy | 1922 | -1943 | City of Pretoria + |
| | O'Neill, Edward James, Merchant Navy | 1915 | -1943 | Dafila + |
| | O'Neill, Daniel, Merchant Navy | 1919 | -1941 | British Security + |
| | O'Neill, Christopher, Merchant Navy | 1896 | -1943 | Melbourne Star + |
| | O'Neill, John, Merchant Navy | 1925 | -1943 | Melbourne Star + |
| | O'Neill, John, Merchant Navy | 1910 | -1944 | Empire Heath + |
| | O'Neill, G.E., Merchant Navy | | | Dinaric |
| | O'Neill, J., RN | | | HMS Courageous (50) |
| | O'Neill, Gilbert William, USNR | | | USS Bristol (DD 453) |
| | O'Neill, Robert Leroy, USNR | 1923 | | USS Fiske (DE 143) |
| | O'Neill, Robert Melvin, USNR | 1923 | | USS Fiske (DE 143) |
| | O'Neill, John P., US Army | 1913 | -1942 | Sicilien + |
| | O'Pray, John A., Merchant Marine | | | Robin Hood |
| | O'Regan, Joseph Michael, RN | 1923 | -1944 | HMS Laforey (G 99) + |
| | O'Regan, William, Merchant Navy | | -1941 | Christian Krohg + |
| | O'Regan, Timothy John, Merchant Navy | 1895 | -1940 | Western Prince + |
| | O'Reilly, Richard Thomas, Merchant Marine | | -1942 | L.J. Drake + |
| | O'Reilly, George, RN | 1915 | -1941 | HMS Barham (04) + |
| | O'Reilly, Richard, Merchant Navy | 1893 | -1940 | Sea Glory + |
| | O'Reilly, William, Merchant Navy | 1906 | -1941 | Hatasu + |
| | O'Reilly, Hugh, Merchant Navy | 1913 | -1942 | Sourabaya + |
| | O'Reilly, Gerald, Merchant Navy | 1921 | -1942 | Trekieve + |
| | O'Reilly, Dan, Merchant Navy | 1899 | -1940 | Leo Dawson + |
| | O'Reilly, Charles T., Merchant Navy | 1908 | -1942 | Thirlby + |
| | O'Reilly, Albert Charles, Merchant Navy | 1927 | -1943 | Polyktor + |
| | O'Reilly, James Brendan, Merchant Navy | 1923 | -1943 | Canadian Star + |
| | O'Reilly, Charles Francis, Merchant Navy | | | Empire Drum |
| | O'Reilly, Patrick Andrew, British Army | 1913 | -1941 | Malaya II + |
| | O'Riordan, Cornelius, Merchant Navy | 1923 | -1943 | Empire Light + |
| | O'Rorke, Charles J.C., RN | | | HMS Courageous (50) |
| | O'Rourke, William John, RN | 1923 | -1944 | HMS Mahratta (G 23) + |
| | O'Rourke, James, Merchant Navy | 1924 | -1944 | Margit + |
| | O'Rourke, Edward James, USNR | | | USS Block Island (CVE 21) |
| | O'Rourke, Francis Xavier, USNR | | | USS Block Island (CVE 21) |
| | O'Rourke, James Joseph, USNR | | | USS Donnell (DE 56) |
| | O'Rourke, James John, Merchant Marine | | -1943 | Dorchester + |
| | O'Shangnessy, A., Merchant Navy | | | Suriname |
| | O'Shea, Michael, NAAFI | 1920 | -1939 | HMS Royal Oak (08) + |
| | O'Shea, Timothy, Merchant Navy | 1918 | -1940 | Otterpool + |
| | O'Shea, Thomas Joseph, Merchant Navy | 1900 | -1941 | Empire Endurance + |
| | O'Shea, Denis, Merchant Navy | 1920 | | Stad Amsterdam |
| | O'Shea, C., RN | | | HMS Zinnia (K 98) |
| | O'Shea, Clarence Joseph, USNR | | | USS Block Island (CVE 21) |
| | O'Sullivan, William A., Merchant Marine | | -1943 | Edward B. Dudley + |
| | O'Sullivan, Patrick Joseph, RN | | -1939 | HMS Courageous (50) + |
| | O'Sullivan, Michael Patrick, RN | | -1943 | HMS Welshman (M 84) + |
| | O'Sullivan, John, RN | 1923 | -1942 | HMS Firedrake (H 79) + |
| | O'Sullivan, Frederick Albert, RN | 1909 | -1942 | HMS Grove (L 77) + |
| | O'Sullivan, Timothy Joseph, RN | 1921 | -1944 | HMS Whitaker (K 580) + |
| | O'Sullivan, Dennis, Merchant Navy | 1905 | -1940 | Athelcrest + |
| | O'Sullivan, Donald Edward, Merchant Navy | 1921 | | Kioto |
| | O'Sullivan, Patrick, Merchant Navy | 1914 | -1944 | Empire Heritage + |
| | O'Sullivan, James, Merchant Navy | 1906 | -1941 | Erna III + |
| | O'Sullivan, James, Merchant Navy | 1908 | -1940 | St. Elwyn + |
| | O'Sullivan, Margaret Mary, British Army | | -1942 | Ceramic + |
| | O'Sullivan, Archibald Denis, Merchant Navy | 1902 | -1942 | Treworlas + |
| | O'Sullivan, Matthew, RN | 1922 | -1943 | Empire Tower + |
| | O'Sullivan, John S., British Army | | -1943 | Egyptian + |
| | O'Sullivan, Rodger John, Merchant Marine | | | Norlantic |
| | O'Sullivan, Patrick Percival, Merchant Navy | | | Venetia |
| | O'Sullivan, James A., Merchant Navy | 1915 | | Koenjit |
| | O'Sullivan, John, British Army | 1912 | | Delfshaven |
| | O'Sullivan, James, Merchant Navy | 1925 | | British Colony |
| | O'Toole, John Bury, Merchant Navy | 1908 | -1940 | Ashcrest + |
| | O'Toole, John William, Merchant Navy | 1917 | -1941 | Canford Chine + |
| | O'Toole, Alfred Patrick, USNR | | | USS Frederick C. Davis (DE 136) |
| | O'Toole, Michael, Merchant Navy | 1920 | -1942 | New York + |
| | Oad, John, Merchant Marine | 1911 | -1942 | Chenango + |
| | Oad, Juri, Merchant Navy | | | Merkur |
| | Oake, Stanley, RN | 1908 | -1945 | HMS Redmill (K 554) + |
| | Oakes, John Kenneth, RN | 1921 | -1942 | HMS Hermione (74) + |
| | Oakes, George, RN | 1918 | -1944 | HMS Mahratta (G 23) + |
| | Oakes, Peter Geoffrey, RAFVR | 1922 | -1942 | Laconia + |
| | Oakes, Norman, Merchant Navy | 1905 | -1941 | Lurigethan + |
| | Oakes, Daniel Webster, USN | | | USS Bristol (DD 453) |
| | Oakey, Allen Douglas, RAN | 1923 | -1941 | HMAS Parramatta (L 44) + |
| | Oakley, Michael James Basile, Merchant Marine | 1902 | -1942 | Raphael Semmes + |
| | Oakley, Victor Sydney, RCNVR | 1921 | -1944 | HMCS Valleyfield (K 329) + |
| | Oakley, Jr., William Edward, Merchant Marine | | -1944 | John A. Poor + |
| | Oakley, Douglas, RNPS | | -1940 | Mohamed Ali El-Kebir + |
| | Oakley, John Thomas, Civilian | 1885 | -1942 | City of Cairo + |
| | Oakley, Derek, Merchant Navy | | -1941 | Hørda + |
| | Oakley, Arthur Elwood, USNR | | -1942 | John D. Gill + |
| | Oakman, Joseph Cecil, RFR | 1902 | -1940 | HMS Forfar (F 30) + |
| | Oaks, Kenneth Courtland, USNR | | | USS Reuben James (DD 245), USS Bristol (DD 453) |
| | Oang Heng, , Merchant Navy | | -1941 | Grootekerk + |
| | Oates, Jack Richard, RN | 1921 | -1942 | HMS Eagle (94) + |
| | Oates, Dudley, RN | 1924 | -1942 | HMS Edinburgh (16) + |
| | Oates, John Charles, RN | 1915 | -1943 | HMS Beverley (H 64) + |
| | Oates, Stephen Machell, RNVR | 1920 | -1944 | HMS Tweed (K 250) + |
| | Oates, Harold, Merchant Navy | 1896 | -1941 | Pandias + |
| | Oates, Thomas Preston, Merchant Navy | 1917 | -1942 | Amarylis + |
| | Oates, George William, Merchant Navy | 1901 | -1941 | Canford Chine + |
| | Oates, Thomas J., Merchant Navy | | | Stigstad |
| | Oates, George M., Merchant Marine | 1918 | | Seakay |
| | Oates, John J., USNR | | | USS Donnell (DE 56) |
| | Oatley, Robert Charles, RN | 1926 | -1944 | HMS Mahratta (G 23) + |
| | Oats, Reginald Arthur, Merchant Navy | 1921 | -1942 | Grangepark + |
| | Obank, G., Merchant Navy | 1913 | | City of Athens |
| | Obard Ali, , Merchant Navy | | -1941 | Shuntien + |
| | Obe, Robert Eugène, Free French Navy | | -1942 | FFL Mimosa (K 11) + |
| | Obee, Eugene C., US Army | | | Dorchester |
| | Oberer, John Francis, Merchant Marine | 1914 | | Naeco |
| | Oberg, Albert Ernest, USN | 1918 | -2010 | USS Jacob Jones (DD 130) |
| | Oberg, Harold E., US Army | | -1943 | Dorchester + |
| | Oborn, Arthur Ray, RM | 1918 | -1942 | HMS Fidelity (D 57) + |
| | Oborn, Richard Eugene, USN | | | USS Block Island (CVE 21) |
| | Obst, Harold L., Civilian | | | Dorchester + |
| | Ocampos, Jose, Merchant Navy | 1893 | -1941 | Rose Schiaffino + |
| | Ocaome, J., | | | South America |
| | Ocasio, Thomas, Merchant Marine | | -1943 | Dorchester + |
| | Occelli, Marius Nicolas, Free French Army | 1909 | -1943 | Sidi-Bel-Abbès + |
| | Ocejo, Saturnino, Merchant Marine | 1903 | | Lehigh |
| | Ochoa, Amado Zuneda, Merchant Marine | 1898 | -1942 | West Ivis + |
| | Ochse, Warren R., US Army | | | Dorchester |
| | Ockleford, Henry Frederick, Merchant Navy | 1919 | -1940 | Victor Ross + |
| | Ockwell, Horace Lindow, British Army | 1913 | -1941 | Newbury + |
| | Ocmore, William, Merchant Marine | | | Steel Scientist |
| | Odd, Hugh Henry, Merchant Navy | | -1941 | Gairsoppa + |
| | Odden, Per W.A., Merchant Navy | | | Bronxville |
| | Oddland, Ingolf, Merchant Navy | 1922 | | Torvanger |
| | Oddsson, Sigurður Jóhann, Merchant Navy | 1903 | -1944 | Godafoss + |
| | Oddsson, Daníel Kr., Fishing Fleet | 1891 | -1941 | Reykjaborg + |
| | Oddsson, Sigurður, Merchant Navy | | -1942 | Fanefjeld + |
| | Oddy, Eric Frederick, RN | | -1942 | HMS Avenger (D 14) + |
| | Oddy, Geoffrey Willink, RN | 1923 | -1944 | HMS LCT-1074 + |
| | Oddy, Frederick Vincent, Merchant Navy | 1909 | -1941 | Calchas + |
| | Odell, Stanley Edward, RN | 1905 | -1942 | HMS Firedrake (H 79) + |
| | Odell, William John, RN | 1913 | -1942 | HMS Firedrake (H 79) + |
| | Odemaere, Pierre Jean Antonius, Merchant Navy | 1900 | | Dempo |
| | Odey, Charles William, RN | 1909 | -1942 | HMS Hecla (F 20) + |
| | Odey Abdillahi, , Merchant Navy | 1910 | -1942 | Empire Prairie + |
| | Odhams, David Noel, Merchant Navy | 1923 | -1944 | Nairung + |
| | Odhner, Claes Johan, Merchant Navy | 1897 | -1941 | Murjek + |
| | Odiong, Alfred Udo, Merchant Navy | 1918 | | Mattawin |
| | Odland, Nils, Merchant Navy | | | Marit |
| | Odland, Sigvald Johan, Merchant Navy | 1907 | | Alexandra Høegh |
| | Odonker, Raphael Drah, Merchant Navy | 1907 | -1941 | Robert L. Holt + |
| | Odu, Florence, Civilian | 1918 | -1943 | Phemius + |
| | Odu, Rosaline, Civilian | 1941 | -1943 | Phemius + |
| | Oduma, Dennis, Nigeria Naval Defence Force | | -1941 | Robert Hughes + |
| | Oehlers, George L., Merchant Navy | 1921 | | Crijnssen, Lebore |
| | Oekar, , Merchant Navy | 1914 | | Kota Tjandi |
| | Oekar, , Merchant Navy | | | Mandalika |
| | Oelgart, Harry, Merchant Marine | | | Onondaga |
| | Oemar, , Merchant Navy | 1903 | | Zaandam |
| | Oemar, , Merchant Navy | | | Jagersfontein |
| | Oemir, , Merchant Navy | | | Jagersfontein |
| | Oen, Olaf Johan Johannesen, Merchant Navy | 1917 | | Mirlo |
| | Oepkes, Jacob Jan Antonie, Merchant Navy | 1879 | | Haulerwijk |
| | Oepkes, Gerrit, Merchant Navy | 1900 | | Towa, Flensburg |
| | Oerlemans, Mathieu, Merchant Navy | | | Mercier |
| | Oerlemans, Frans, Merchant Marine | 1888 | | Lubrafol |
| | Oertlin, Jules, Merchant Navy | | -1940 | Orania + |
| | Oertling, Harry Grothann, Merchant Marine | 1887 | -1962 | Comol Rico |
| | Oesin, , Merchant Navy | 1918 | -1942 | Zaandam + |
| | Oesman, , Merchant Navy | | | Jagersfontein |
| | Oesman, , Merchant Navy | | | Palima |
| | Oest-Larsen, Birger, Merchant Marine | 1920 | -1942 | Crusader + |
| | Oetelmans, P.M.F., Royal Dutch Navy | | | Colombia |
| | Oever, Jan van den, Merchant Navy | 1898 | -1942 | Zaandam + |
| | Oever, Paulus Johannes van den, Merchant Navy | 1921 | -1943 | Poelau Roebiah + |
| | Oever, Petrus Jacobus van den, Merchant Navy | 1887 | | Dempo |
| | Oever, A.W. van den, Royal Dutch Navy | | | Colombia |
| | Oewie, , Merchant Navy | | | Jagersfontein |
| | Ofchinsky, Eric, Merchant Navy | | | Tarifa |
| | Offenbacher, Wilbert H., USNR | | | USS LST-333 |
| | Offenbeek, Gerardus van, Merchant Navy | 1907 | | Bodegraven |
| | Offenberg, Gérard, Merchant Navy | | | Alex van Opstal |
| | Offer, Charles Henry, RN | 1919 | -1939 | HMS Royal Oak (08) + |
| | Officer, Albert Black, Merchant Navy | 1916 | -1940 | Sheaf Mead + |
| | Offside, Joseph, Merchant Navy | 1899 | -1941 | Belcrest + |
| | Ofsonka, Jr., Charles P., US Army | | -1944 | Leopoldville + |
| | Oftedahl, Reider, Merchant Marine | 1892 | | Stanvac Palembang, Robert E. Lee |
| | Oftedahl, Leif, Merchant Navy | 1904 | -1943 | Nortind + |
| | Oftedahl, Leif, Merchant Navy | | | Norland |
| | Oftedal, Alf, Merchant Marine | 1885 | -1942 | Mariana + |
| | Oftedal, Harald, Merchant Navy | | | Hamlet |
| | Oftenes, Nils, Merchant Navy | 1922 | -1942 | Belize + |
| | Ogden, Gordon Raymond, RN | 1923 | -1939 | HMS Royal Oak (08) + |
| | Ogden, Clarence, RN | 1915 | -1941 | HMS Zinnia (K 98) + |
| | Ogden, John, Merchant Navy | 1916 | -1941 | Toronto City + |
| | Ogden, James Frederick, Merchant Navy | 1913 | -1941 | Sirikishna + |
| | Ogden, Robert Arthur, Merchant Navy | 1926 | -1945 | King Edgar + |
| | Ogenio, Cipriano, Merchant Marine | | -1942 | Coamo + |
| | Oger, Jean, Vichy French Navy | | -1940 | Sfax (Q 182) + |
| | Oger, Marcel, Merchant Navy | | -1941 | Limbourg + |
| | Ogg, Edward Moss, Merchant Navy | 1883 | -1942 | Edencrag + |
| | Ogg, Robert George, RAFVR | 1921 | -1941 | Anselm + |
| | Ogg, John Thompson, Merchant Navy | 1904 | | British Freedom |
| | Ogier, Frederick, US Army | | | Buchanan |
| | Ogilvie, Arthur, Merchant Navy | 1883 | -1939 | Menin Ridge + |
| | Ogilvie, Frederick James, Merchant Navy | 1879 | -1941 | Zealandic + |
| | Oginski, Michal, Polish Army | | -1942 | Laconia + |
| | Ogle, Robert, RN | 1921 | -1941 | HMS Barham (04) + |
| | Ogle, William Crammon, RN | 1921 | -1942 | HMS Culver (Y 87) + |
| | Ogle, B.A., Christine Emma, WRNS | 1907 | -1941 | Aguila + |
| | Ogle, Andrew William, Merchant Navy | 1920 | -1945 | Empire Gold + |
| | Ogle, Cyril Alexander, Merchant Marine | 1890 | -1942 | Oakmar + |
| | Oglesby, Buel Bennett, USCGR | | -1944 | USS Menges (DE 320) + |
| | Ograyensek, Rudolph, USNR | | -1943 | USS Buck (DD 420) + |
| | Ogrodnik, Raymond Albert, USNR | | | USS Block Island (CVE 21) |
| | Ogten, Johan Cornelis van, Merchant Navy | 1918 | | Mandalika |
| | Ogui Albert, , Free French Army | | -1943 | Sidi-Bel-Abbès + |
| | Ogunbiyi, Samuel Akiyemi, Merchant Navy | 1899 | -1943 | Marcella + |
| | Ohar, John, USCG | | -1944 | USS Leopold (DE 319) + |
| | Ohlsen, Francis W., USCG | | -1942 | USS Muskeget (WAG 48) + |
| | Ohlsen, Rikmond Rudolf, Merchant Navy | 1923 | -1942 | Leikanger + |
| | Ohlsson, Per Emil, Merchant Navy | 1896 | -1940 | Nils Gorthon + |
| | Ohlsson, Carl Oskar, Merchant Navy | 1894 | -1940 | Kayeson + |
| | Ohlsson, Ejnar Bernhard, Merchant Navy | 1908 | -1941 | Korshamn + |
| | Ohlsson, Harry M., Merchant Navy | 1921 | -1941 | Venezuela + |
| | Ohma, Leif, Merchant Navy | | | Torny |
| | Ohma, Leif, Merchant Navy | | | Corneville |
| | Ohman, Eric Dorman, Merchant Navy | 1919 | -1943 | Aelybryn + |
| | Ohman, Elis, Merchant Navy | | | Everalda |
| | Ohnigian, Suran, USNR | | | USS LST-348 |
| | Ohr, Aimé, Royal Dutch Navy | 1909 | -1942 | HNMS Isaac Sweers (G 83) + |
| | Ohrt, Jr., Charles Newton, USN | 1911 | -1943 | USS Dorado (SS 248) + |
| | Oiring, Morris Nathan, RCAF | | -1942 | Caribou + |
| | Oispuu, Erich L., Merchant Navy | | -1943 | Neva + |
| | Oittinen, Ilmari, Merchant Navy | 1912 | -1942 | Torungen + |
| | Ojalvo, Leo, USNR | | -1944 | USS LST-359 + |
| | Ojea, Juan, Merchant Marine | | | Honomu |
| | Ojeda, Ramon, Merchant Marine | 1920 | -1942 | Muskogee + |
| | Ojen, Enrique, Merchant Marine | | -1942 | Heredia + |
| | Ojo, , Merchant Navy | | -1942 | Ilorin + |
| | Ojo, Joshua, Civilian | 1914 | -1943 | Phemius + |
| | Ojo, Asher, Merchant Navy | 1914 | -1941 | Dunkwa + |
| | Ojserkis, Charles, USNR | | -1942 | USS Cythera (PY 26) + |
| | Okali, S.O., Merchant Navy | 1916 | -1942 | Henry Stanley + |
| | Okaro, Thomas, Merchant Navy | 1919 | -1941 | Seaforth + |
| | Okasha, Ahmed, Merchant Marine | 1904 | -1942 | Scapa Flow + |
| | Oke, Frederick George, RCNVR | 1921 | -1944 | HMCS Valleyfield (K 329) + |
| | Okechuku, Nelson, Merchant Navy | 1917 | -1941 | Seaforth + |
| | Oker, Harley Duane, Merchant Marine | 1921 | -1943 | Walter Q. Gresham + |
| | Okeson, Emil, Merchant Marine | 1894 | -1942 | Chenango + |
| | Okhuizen, Henrietta A., Civilian | 1903 | -1940 | Eurymedon + |
| | Oksanen, Karl, Merchant Marine | | | Coloradan |
| | Oksen, Robert Carlton, Merchant Marine | 1913 | -1942 | Muskogee + |
| | Olachia, Anselmo Bueno, Merchant Marine | | -1942 | R.P. Resor + |
| | Olad Ali, , Merchant Navy | 1912 | -1942 | Empire Turnstone + |
| | Olaf, Karlsen, Merchant Navy | | | Gimle |
| | Olafsen, Erling Johan, Merchant Marine | 1903 | -1942 | Balladier + |
| | Olafsen, Arve, Merchant Navy | | | Leiv Eiriksson |
| | Olafsen, Arnljot Geline, Merchant Navy | 1918 | -1942 | Bayard + |
| | Olafsen, Trygve, Merchant Navy | | | Trolla |
| | Olafsen, Alf Melchior, Merchant Navy | 1888 | -1942 | Fagersten + |
| | Olafsen, Einar, Merchant Navy | | | Kosmos II |
| | Olafsen, Arnt, Merchant Navy | | | Daghild |
| | Olafsen, Odd Harry, Merchant Navy | 1918 | | Leiesten |
| | Olafsen, Edward William, Merchant Navy | 1922 | -1943 | Baron Kinnaird + |
|
| | Ólafsson, Þórir, Merchant Navy | 1905 | -1944 | Godafoss + |
| | Ólafsson, Ólafur Björn, Civilian | | | Dettifoss |
| | Ólafsson, Eiríkur, Merchant Navy | | | Dettifoss |
| | Ólafsson, Hafliði, Merchant Navy | 1894 | -1941 | Hekla + |
| | Ólafsson, Sigurður, Merchant Navy | | | Hekla |
| | Ólafsson Olsen, Oddur Stefán, Merchant Navy | 1913 | | Godafoss |
|
| | Olaisen, Olav Bertrand, Merchant Navy | 1907 | -1940 | Neptunian + |
| | Olaisen, Ole, Merchant Navy | | | Sandanger |
| | Olaisen, Håkon, Merchant Navy | 1910 | -1943 | Storaas + |
| | Olamuyah, Akintola, Civilian | 1919 | -1943 | Phemius + |
| | Olander, Erling Sæther, Merchant Navy | 1918 | -1944 | Tarifa + |
| | Olando, Carrol Alfanso, Merchant Marine | | -1942 | Illinois + |
| | Olar, Benjamin Joseph, USN | | -1943 | Sunoil + |
| | Olarra, Louis, Merchant Navy | 1920 | -1942 | Empire Surf + |
|
| | Ólason, Friðgeir, Civilian | 1912 | -1944 | Godafoss + |
|
| | Olausen, Karl H., Merchant Navy | | | Bronxville |
| | Olausen, Ludvig, Merchant Navy | | -1943 | Christian Michelsen + |
| | Olaussen, Erling, Merchant Navy | 1917 | -1942 | Belize + |
| | Olaussen, Erling Edvard, Merchant Navy | 1900 | -1942 | Ringstad + |
| | Olaussen, Sigurd, Merchant Navy | | | Viva |
| | Olaussen, Harald Bjerke, Merchant Navy | 1920 | -1941 | Polyana + |
| | Olaussen, Rolf, Merchant Navy | 1912 | -1942 | Bris + |
| | Olausson, Allan, Merchant Navy | | | Ferm |
| | Olausson, Karl Arvid, Merchant Navy | 1883 | -1940 | Liana + |
| | Olav, Evensen, Merchant Navy | | | Gimle |
| | Olavesen, William Marensius, Merchant Navy | 1901 | -1940 | Randsfjord + |
| | Olavesen, Georg Henry, Merchant Navy | 1899 | -1940 | Pacific President + |
| | Olavesen, Johan Olaf, Merchant Navy | 1887 | -1942 | Vibran + |
| | Olawumi, John Alfred, Merchant Navy | 1895 | -1943 | Marcella + |
| | Olaydon, Stanley, Merchant Navy | 1920 | | Loch Don |
| | Olby, Derek Morley, RN | | -1943 | HMS Holcombe (L 56) + |
| | Olcese, Attilio, Merchant Navy | | -1942 | Nova Scotia + |
| | Old, Ernest George, Merchant Navy | | | Tresillian |
| | Oldakoff, W., Merchant Navy | 1916 | -1939 | Stanbrook + |
| | Oldbury, Arthur Joseph, Merchant Navy | 1921 | -1940 | Eurymedon + |
| | Oldeide, Herman, Merchant Navy | | | Breñas |
| | Olden, Ika, Civilian | 1908 | -1940 | City of Benares + |
| | Olden, Rudolph, Civilian | 1885 | -1940 | City of Benares + |
| | Oldenhove, Johannes, Merchant Navy | 1917 | | Bennekom, Suriname |
| | Older, Ronald, Merchant Navy | 1922 | -1940 | Sulaco + |
| | Oldfield, Thomas Edward, RN | 1925 | -1944 | HMS Laforey (G 99) + |
| | Oldfield, John, RN | 1923 | -1942 | HMS Matabele (G 26) + |
| | Oldfield, William Alfred, RN | 1923 | -1944 | HMS Whitaker (K 580) + |
| | Oldfield, William, Merchant Navy | 1890 | -1942 | Abosso + |
| | Oldfield, Colin, RN | 1923 | -1942 | Stornest + |
| | Oldfield, George Selwyn, FAA | 1921 | -1941 | Almeda Star + |
| | Oldfield, Thomas, Merchant Navy | 1901 | -1942 | Adellen + |
| | Oldham, R., Merchant Navy | 1900 | | Arandora Star |
| | Oldman, Roy James Emmanuel, Merchant Navy | 1920 | -1940 | Ashcrest + |
| | Oldnall, Kenneth James, RN | 1924 | -1943 | HMS Cuckmere (K 299) + |
| | Ole, Sande, Merchant Navy | | | Gimle |
| | Oleana, Gregorio, Merchant Navy | 1897 | | Hector |
| | Olender, Frank, USN | | -1943 | USS Skill (AM 115) + |
| | Olesen, Oscar Imanuel, Merchant Navy | 1911 | -1941 | Susan Mærsk + |
| | Olesen, Jens M., Merchant Marine | 1902 | | Thalia |
| | Olesnevich, George John, USN | | -1942 | USS Atik (AK 101) + |
| | Olexa, Steve, USN | | | USS Reuben James (DD 245) |
| | Olff, Oscar George, Merchant Navy | 1912 | | Suriname |
| | Olff, Alva John, Merchant Navy | 1916 | -1942 | Suriname + |
| | Olgers, G.P., Royal Dutch Navy | | | Colombia |
| | Olic, Ivan, Merchant Navy | 1911 | | Trepca |
| | Oliéric, André, Free French Army | 1918 | -1943 | Sidi-Bel-Abbès + |
| | Oliffe-Smith, Fred, Civilian | 1894 | -1941 | Avoceta + |
| | Oliffe-Smith, Gilberte, Civilian | 1903 | -1941 | Avoceta + |
| | Olin, Carl, Merchant Navy | | | San Gerardo |
| | Olin, Anton, Merchant Navy | 1893 | -1940 | Tregenna + |
| | Olinger, Robert Sam, USNR | | | Pillory |
| | Oliphant, Jr., Hugh Boyer, USNR | | -1942 | East Indian + |
| | Oliphant, William Edward, British Army | 1898 | -1941 | Silvercedar + |
| | Oliva, Margoiot, Merchant Marine | | -1942 | Castilla + |
| | Oliva, Angelo, Regio Esercito | 1920 | -1942 | Laconia + |
| | Oliva, Aniello, Regio Esercito | 1920 | -1942 | Laconia + |
| | Oliva, Realino, Regio Esercito | 1920 | -1942 | Laconia + |
| | Olivant, Cecil Herbert, RN | 1901 | -1941 | Saugor + |
| | Olivarez, Aurelio Gomiz, Merchant Navy | 1899 | | Induna |
| | Olivari, Stansbury Andrea, Merchant Navy | 1917 | -1942 | Baron Ogilvy + |
| | Olivas, Magdaleno, US Army | | -1944 | Leopoldville + |
| | Olive, John Roland, RN | 1912 | -1940 | HMS Exmouth (H 02) + |
| | Oliveira, Antonio D.R., Merchant Navy | 1910 | -1942 | Empire Gilbert + |
| | Oliveira, José Martins de, Merchant Navy | | | Tamandaré |
| | Oliveira, Sivirino Rodrigues de, Merchant Navy | | | Pedrinhas |
| | Oliveira de Arauje, Antonio, Merchant Navy | 1920 | | Arabutan |
| | Olivelli, A, Civilian | | -1940 | Arandora Star + |
| | Oliver, Ralph Albert, Merchant Marine | | -1943 | Puerto Rican + |
| | Oliver, Edwin Ambrose, RN | 1888 | -1939 | HMS Courageous (50) + |
| | Oliver, Geoffrey Nigel, RN | 1898 | | HMS Hermione (74) |
| | Oliver, Maurice Faulkman, RCNR | | | HMCS Chebogue (K 317) |
| | Oliver, Oswald, RN | 1913 | -1940 | HMS Spearfish (N 69) + |
| | Oliver, Cyril Henry, RN | 1902 | -1941 | HMS Dunedin (D 93) + |
| | Oliver, Frederick John, RN | 1913 | -1942 | HMS Hermione (74) + |
| | Oliver, Lawrence Edgar, RN | 1915 | -1942 | HMS Hermione (74) + |
| | Oliver, Roy, Merchant Navy | 1913 | | Sea Gull D. |
| | Oliver, Leslie, RN | 1915 | -1942 | HMS Matabele (G 26) + |
| | Oliver, Walter Henry, RN | 1920 | -1941 | HMS Manistee (F 104) + |
| | Oliver, Norbert, RAN | 1904 | -1941 | HMAS Parramatta (L 44) + |
| | Oliver, John Desmond, RN | 1914 | -1944 | HMS Kite (U 87) + |
| | Oliver, Howard Fullerton, USNR | 1924 | -1943 | Arthur Middleton + |
| | Oliver, Curtis Ismal, USNR | | -1943 | USS Leary (DD 158) + |
| | Oliver, Manuel Charles, USNR | | -1944 | USS LST-348 + |
| | Oliver, Norman, British Army | 1922 | -1942 | Pelayo + |
| | Oliver, James Ernest, British Army | 1910 | -1942 | Empire Attendant + |
| | Oliver, John, Merchant Navy | 1879 | -1940 | Blairmore + |
| | Oliver, Maurice, Merchant Navy | 1925 | -1942 | Winamac + |
| | Oliver, Henry Ronald, Merchant Navy | 1911 | -1941 | Empire Crossbill + |
| | Oliver, Cyril, Merchant Navy | 1925 | -1942 | New York + |
| | Oliver, Stuart Alexander, Merchant Navy | 1911 | -1939 | Darino + |
| | Oliver, John George, Merchant Navy | 1920 | -1940 | Polzella + |
| | Oliver, John Richard, Merchant Navy | 1918 | -1941 | Almeda Star + |
| | Oliver, William, Merchant Navy | 1919 | -1941 | Holystone + |
| | Oliver, Joseph, Merchant Navy | 1920 | -1941 | Holmelea + |
| | Oliver, George Edward, Merchant Navy | 1919 | -1942 | Opawa + |
| | Oliver, Harold Ernest, Merchant Navy | 1919 | -1942 | Biela + |
| | Oliver, James, Merchant Navy | 1899 | -1944 | Olga E. Embiricos + |
| | Oliver, George Henry, British Army | 1916 | | Nerissa |
| | Oliver, William Francis, USN | | | USS Gannet (AVP 8) |
| | Oliver, Sidney George, British Army | 1912 | -1942 | New York + |
| | Oliver, George Henry, British Army | 1909 | -1944 | Empire Lancer + |
| | Oliver, J.L., Merchant Navy | | | Sheaf Mount |
| | Oliver, Cornelius Webster, Merchant Navy | | | Sheaf Crown |
| | Oliver, Roy Conley, USN | | | USS Salinas (AO 19) |
| | Oliver, Robert LeRoy, USNR | | | USS Block Island (CVE 21) |
| | Oliver, Anthony Alves, USNR | | -1944 | USS LST-133 + |
| | Oliver, Hugh C., Merchant Marine | | -1942 | J.A. Mowinckel |
| | Oliver, Richard Davidson, British Army | 1918 | -1944 | HMS LST-362 + |
| | Oliver, Stanley Herbert, Merchant Marine | 1907 | -1996 | Texan |
| | Oliverio, Anthony, USNR | | -1943 | Gulfstate + |
| | Olivero, Rafael, Merchant Marine | | -1942 | Margaret + |
| | Oliverre, Jim, Merchant Navy | | | Sea Gull D. |
| | Olivier, S., Civilian | 1914 | -1942 | Abosso + |
| | Olivier, Fulp, Merchant Navy | 1914 | | Zuiderkerk, Benakat |
| | Olivier Santibáñez, Carlos Alberto, Merchant Navy | | -1942 | Tolten + |
| | Oliviera, R.J., Merchant Marine | 1915 | -1941 | Longtaker + |
| | Olivieri, Aurelio, Regio Esercito | 1910 | -1942 | Laconia + |
| | Olivo, Juan Ramon, Merchant Marine | 1900 | | Alcoa Pathfinder |
| | Olkio, Kalevi, Merchant Navy | | | Minister Wedel |
|
| | Õlle, Rudolf, Merchant Navy | | -1939 | Agu + |
|
| | Ollefers, David H., Merchant Navy | 1908 | | Volendam |
| | Ollerenshaw, Henry, RN | 1921 | -1941 | HMS Barham (04) + |
| | Ollerenshaw, Daniel, RN | 1921 | -1943 | HMS P-615 + |
| | Ollerton, John, RN | 1911 | -1944 | HMS Asphodel (K 56) + |
| | Ollerup, Hans Anton Ditlev, Merchant Navy | 1914 | -1942 | Hans Egede + |
| | Olley, Ivor Roy William, RNVR | 1915 | -1942 | HMS Avenger (D 14) + |
| | Olley, Alfred George, RNVR | | -1940 | HMS Forfar (F 30) + |
| | Ollis, Reginald Keith, RCAF | 1923 | -1943 | Amerika + |
| | Olliver, Noel, Merchant Navy | 1901 | -1942 | Prescodoc + |
| | Olliver, Leonard Edwin, RNVR | 1918 | -1941 | HMS Barham (04) + |
| | Ollivier, Jean François, Free French Navy | | -1942 | FFL Mimosa (K 11) + |
| | Olliviere, Roger, Merchant Navy | 1909 | -1942 | Charles L.D. + |
| | Ollivro, Georges Francis, Free French Navy | 1923 | -1945 | FFL L´Enjoue (W 44) + |
| | Olman, Karl, Merchant Navy | | | Spind |
| | Olmen, Karel David van, Merchant Navy | 1913 | -1942 | Paulus Potter, Serooskerk + |
| | Olmetti, John, Merchant Navy | 1916 | -1942 | Goolistan + |
| | Olmo, Jose Antonio, Merchant Marine | | -1943 | Dorchester + |
| | Olmstead, Donald Everett, USN | | -1941 | USS Reuben James (DD 245) + |
| | Olney, Sidney James, RN | 1920 | -1942 | Nurmahal + |
| | Olofson, Gustaf Adolph, Merchant Marine | | -1942 | Scottsburg + |
| | Olofsson, Einar Albin, Merchant Navy | 1910 | -1943 | Milos + |
| | Olofsson, Nils, Merchant Navy | 1911 | -1940 | Lars Magnus Trozelli + |
| | Olofsson, Gösta Elof, Merchant Navy | 1920 | -1943 | Vaalaren + |
| | Olofsson, Olof Alfred, Merchant Navy | 1902 | | Amerikaland |
| | Olsen, Benjamin Michael, Merchant Marine | | -1942 | I.C. White, Allan Jackson + |
| | Olsen, Ole Andreas, Merchant Marine | | -1942 | Caddo + |
| | Olsen, Sam, Merchant Marine | | -1942 | Gulfpenn + |
| | Olsen, Olaf Z., Merchant Marine | | -1942 | Hagan + |
| | Olsen, John H., Merchant Marine | | -1943 | James Sprunt + |
| | Olsen, Theodore Thomas, Merchant Marine | 1918 | -1942 | John R. Williams + |
| | Olsen, Ragnvald, Merchant Marine | | -1943 | Louise Lykes + |
| | Olsen, Karl Ragnar, Merchant Marine | | -1942 | Munger T. Ball + |
| | Olsen, Ragnval, Merchant Marine | | -1942 | Nathaniel Hawthorne + |
| | Olsen, Emil Tonnesen, Merchant Marine | 1894 | -1942 | Pan Massachusetts + |
| | Olsen, Olaf, Merchant Marine | 1915 | -1942 | Susana + |
| | Olsen, Jens Fagstrup, Merchant Marine | | -1942 | Suwied + |
| | Olsen, Henning Peter Kohler, Merchant Navy | 1909 | -1942 | Chr. J. Kampmann + |
| | Olsen, George Frederick, Merchant Navy | 1927 | -1944 | Cornwallis + |
| | Olsen, Niels, Merchant Navy | 1883 | -1941 | Rinda + |
| | Olsen, Gjert Sofus, Merchant Navy | | | Havsten |
| | Olsen, Peder Johan, Merchant Navy | | | Malmanger |
| | Olsen, John Martin, USN | | -1942 | Steel Navigator + |
| | Olsen, Olav Konrad, Royal Norwegian Navy | | -1941 | HNoMS Bath (I 17) + |
| | Olsen, Håkon Alfred, Royal Norwegian Navy | | -1942 | HNoMS Montbretia (K 208) + |
| | Olsen, Odd Harry Meier, Royal Norwegian Navy | | -1942 | HNoMS Montbretia (K 208) + |
| | Olsen, Thoralf Johnny, Royal Norwegian Navy | | -1942 | HNoMS Montbretia (K 208) + |
| | Olsen, Thorleif Anker, Royal Norwegian Navy | | -1942 | HNoMS Montbretia (K 208) + |
| | Olsen, Trygve Olai, Royal Norwegian Navy | | -1942 | HNoMS Montbretia (K 208) + |
| | Olsen, Sigurd Wilfred, Merchant Navy | 1902 | -1940 | Pecten + |
| | Olsen, Harald Frederik, Merchant Marine | 1905 | -1942 | Friar Rock + |
| | Olsen, Torger, Merchant Marine | 1887 | -1943 | Gulftrade |
| | Olsen, Finnur, Merchant Navy | 1911 | -1942 | Boringia + |
| | Olsen, Harry, Merchant Navy | 1906 | -1942 | Boringia + |
| | Olsen, Johan I., Merchant Navy | | | Altair |
| | Olsen, Erling, Merchant Navy | 1916 | | Andrea Brøvig, Robert E. Lee |
| | Olsen, Rasmus, Merchant Navy | | -1942 | Athene + |
| | Olsen, Reidar, Merchant Navy | | | Belmoira |
| | Olsen, Tore Edvind, Merchant Navy | | | Belmoira |
| | Olsen, Lorange Magnus Jonsen, Merchant Navy | | -1941 | Christian Krohg + |
| | Olsen, Just, Merchant Navy | | | Crux |
| | Olsen, Sverre, Merchant Navy | | | Crux |
| | Olsen, O., Merchant Navy | | | Eli Knudsen |
| | Olsen, Johannes Marius, Merchant Navy | 1877 | | Høegh Giant, Robert E. Lee |
| | Olsen, Reidar, Merchant Navy | 1920 | | Høegh Giant, Robert E. Lee |
| | Olsen, Georg Severin, Merchant Navy | 1909 | -1940 | Italia + |
| | Olsen, Knut Langtveit, Merchant Navy | 1923 | -1940 | Italia + |
| | Olsen, Ottar Normann, Merchant Navy | 1922 | -1942 | Kongsgaard, Kongsgaard + |
| | Olsen, Reidar Oliver, Merchant Navy | 1906 | -1942 | Kongsgaard, Kongsgaard + |
| | Olsen, Peder, Merchant Navy | 1910 | | Lenda |
| | Olsen, Kolbjørn Steen, Merchant Navy | 1894 | -1968 | Nidarnes |
| | Olsen, Olav, Merchant Navy | | | Pleasantville |
| | Olsen, Edvin Anker, Merchant Navy | 1907 | | Ranella |
| | Olsen, Harald, Merchant Navy | | | Ranella |
| | Olsen, Åge, Merchant Navy | | | Slemdal |
| | Olsen, Arthur, Merchant Navy | | | Slemdal |
| | Olsen, Martel, Merchant Navy | | | Slemdal |
| | Olsen, Olaf, Merchant Navy | | | Slemdal |
| | Olsen, Aksel Robert Jentoft, Merchant Navy | 1900 | | South Africa |
| | Olsen, Einar, Merchant Navy | 1909 | | Torvanger |
| | Olsen, Hjørdis E., Merchant Navy | | | Tudor |
| | Olsen, Arne Waldemar, Merchant Navy | 1904 | -1941 | Vigrid + |
| | Olsen, Olaf, Merchant Navy | | | B.P. Newton |
| | Olsen, Kristian, Merchant Navy | | | Hero |
| | Olsen, Håkon, Merchant Navy | | | Inga I |
| | Olsen, Henning Jørgen, Merchant Navy | 1916 | -1942 | Peter Mærsk + |
| | Olsen, Jørgen Levin, Merchant Navy | 1922 | -1942 | Peter Mærsk + |
| | Olsen, Sigvald Anton, Merchant Navy | 1886 | -1944 | Empire Heritage + |
| | Olsen, Jens Villy Johannes, Merchant Navy | 1920 | -1941 | Erna III + |
| | Olsen, Christen Kobberø, Merchant Navy | 1918 | -1942 | Lifland + |
| | Olsen, T.P., Merchant Navy | | | Helen Moller |
| | Olsen, Thorbjørn, RNR | 1900 | -1942 | HMS Sotra + |
| | Olsen, Ansgar S. Foss, Merchant Marine | 1910 | -1942 | Steel Age + |
| | Olsen, Harry Justinius, Merchant Navy | 1897 | -1939 | Vistula + |
| | Olsen, Ole, Merchant Navy | 1885 | -1940 | Hedrun + |
| | Olsen, Johan Berg, Merchant Navy | | -1940 | Alida Gorthon + |
| | Olsen, Aksel, Merchant Navy | | | Gro |
| | Olsen, Severin, Merchant Navy | | | Hird |
| | Olsen, Harald Angell, Merchant Navy | 1922 | | Vestvard |
| | Olsen, Gudmund Johan, Merchant Navy | 1879 | -1940 | Nina Borthen + |
| | Olsen, Jens Johan, Merchant Navy | | -1940 | Nina Borthen + |
| | Olsen, Peder Kornelius, Merchant Navy | | -1940 | Nina Borthen + |
| | Olsen, Ottar Emil, Merchant Navy | | | Touraine |
| | Olsen, Kurt, Merchant Navy | | | Brandanger |
| | Olsen, Frank, Merchant Navy | | | Davanger |
| | Olsen, Oskar Marinius, Merchant Navy | | -1940 | Salonica + |
| | Olsen, Trygve Andreas, Merchant Navy | | -1940 | Daphne + |
| | Olsen, Sigurd Waldemar, Merchant Navy | 1897 | -1940 | Skrim + |
| | Olsen, Sverre Kure, Merchant Navy | | | Risanger |
| | Olsen, Oluf Kristian, Merchant Navy | | | Inger |
| | Olsen, Eivind, Merchant Navy | | | Spind |
| | Olsen, Erling, Merchant Navy | | -1941 | Stargard + |
| | Olsen, Johan, Merchant Navy | | -1941 | Barbro + |
| | Olsen, Ragnar, Merchant Navy | | -1941 | Barbro + |
| | Olsen, Arne, Merchant Navy | | -1941 | Siremalm + |
| | Olsen, Gunvald, Merchant Navy | | -1941 | Siremalm + |
| | Olsen, Konrad, Merchant Navy | 1899 | -1941 | Siremalm + |
| | Olsen, Brinck, Merchant Navy | | | Hellen |
| | Olsen, Lars, Merchant Navy | | | Hellen |
| | Olsen, Ole L., Merchant Navy | | | Hellen |
| | Olsen, Hjalmar Johannes, Merchant Navy | 1907 | | Tyr, Havsten |
| | Olsen, Ole Martin, Merchant Navy | | | Havsten |
| | Olsen, Petter, Merchant Navy | | | Havsten |
| | Olsen, Erling, Merchant Navy | | | Arthur W. Sewall |
| | Olsen, Hans, Merchant Navy | | | Breñas |
| | Olsen, Olaf, Merchant Navy | | | Breñas |
| | Olsen, Aksel Bernhard, Merchant Navy | 1886 | -1942 | Malmanger + |
| | Olsen, Johan Anker, Merchant Navy | | | Malmanger |
| | Olsen, Dagfinn, Merchant Navy | 1919 | | Mirlo |
| | Olsen, Harald, Merchant Navy | | | Triton |
| | Olsen, Harry Adolf, Merchant Navy | | | Triton |
| | Olsen, K., Merchant Navy | | | Thelma |
| | Olsen, Ove, Merchant Navy | | | Thelma |
| | Olsen, Olaf B., Merchant Navy | | | Vardaas |
| | Olsen, Arne, Merchant Navy | 1925 | | Sveve |
| | Olsen, Bjarne, Merchant Navy | | | Sveve |
| | Olsen, Arne Hjalmar, Merchant Navy | | | Fjordaas |
| | Olsen, Kristian, Merchant Navy | | | Hindanger |
| | Olsen, Walter, Merchant Navy | | | Hindanger |
| | Olsen, Harald Adolf, Merchant Navy | 1918 | -1942 | Sørholt + |
| | Olsen, Walter Gabriel Wisback, Merchant Navy | 1910 | | Sørholt |
| | Olsen, Thorleif, Merchant Navy | | -1942 | Vibran + |
| | Olsen, Leif, Merchant Navy | 1917 | | Trafalgar |
| | Olsen, Ole, Merchant Navy | 1920 | | Trafalgar |
| | Olsen, Rolf, Merchant Navy | 1917 | | Trafalgar |
| | Olsen, Trygve Gotfred, Merchant Navy | 1888 | -1949 | Trafalgar |
| | Olsen, Erling Frithjof Wisback, Merchant Navy | 1912 | | Primero |
| | Olsen, Johan Petter, Merchant Navy | 1916 | | Primero |
| | Olsen, Søren, Merchant Navy | 1923 | | Primero |
| | Olsen, Kjell, Merchant Navy | | | Kosmos II |
| | Olsen, Oliver, Merchant Navy | | | Kosmos II |
| | Olsen, Olaf, Merchant Navy | | | Alaska |
| | Olsen, Halvor Holtskog, Merchant Navy | 1902 | -1942 | Thorshavet + |
| | Olsen, Hilmar, Merchant Navy | | | Thorshavet |
| | Olsen, Rolf, Merchant Navy | | | Astrell |
| | Olsen, Egil, Merchant Navy | 1923 | -1974 | Maloja |
| | Olsen, Fredrik Farmann, Merchant Navy | 1920 | | Maloja |
| | Olsen, Henry Georg, Merchant Navy | | | Maloja |
| | Olsen, Alf G., Merchant Navy | | | Nidarland |
| | Olsen, Ole Meyer, Merchant Navy | 1902 | | Tortugas |
| | Olsen, Even, Merchant Navy | | | Prins Harald |
| | Olsen, Rolf, Merchant Navy | | | Prins Harald |
| | Olsen, Karl Andreas, Merchant Navy | | -1942 | Bello + |
| | Olsen, Ole Jørgen, Merchant Navy | | -1942 | Bello + |
| | Olsen, Sverre, Merchant Navy | | -1942 | Bello + |
| | Olsen, Leif, Merchant Navy | | -1942 | Ingerfem + |
| | Olsen, Bjørn, Merchant Navy | 1924 | -1942 | Norse King + |
| | Olsen, Leif Henry Johan, Merchant Navy | 1898 | -1942 | Norse King + |
| | Olsen, Birger Horne, Merchant Navy | | | Fernhill |
| | Olsen, Nicolai Lindtner, Merchant Navy | 1909 | -1945 | Fernhill, Spinanger + |
| | Olsen, Sverre, Merchant Navy | 1899 | | Eva |
| | Olsen, Nils, Merchant Navy | | | Skjelbred |
| | Olsen, Ole Alfred, Merchant Navy | | | Christian Michelsen |
| | Olsen, Bernt, Merchant Navy | | | Litiopa |
| | Olsen, Trygve, Merchant Navy | | | Litiopa |
| | Olsen, Hans, Merchant Navy | | -1943 | Hallfried + |
| | Olsen, Ragnar, Merchant Navy | | | Fjordheim |
| | Olsen, Arthur Emanuel, Merchant Navy | 1890 | -1940 | Manx + |
| | Olsen, Johan Rudolf, Merchant Navy | 1904 | -1940 | Manx + |
| | Olsen, Georg Henry, Merchant Navy | 1895 | -1940 | Fagerheim + |
| | Olsen, Olaf Andreas, Merchant Navy | 1915 | -1940 | Fagerheim + |
| | Olsen, Leif, Merchant Navy | 1898 | -1940 | Foxen + |
| | Olsen, Edvar Johan, Merchant Navy | 1882 | -1940 | Telnes + |
| | Olsen, Martin, Merchant Navy | 1920 | -1940 | Telnes + |
| | Olsen, Kåre, Merchant Navy | 1911 | -1940 | Segovia + |
| | Olsen, Ole, Merchant Navy | 1909 | -1940 | Segovia + |
| | Olsen, Ole Martin Garder, Merchant Navy | 1920 | -1940 | Segovia + |
| | Olsen, Olav Marthon, Merchant Navy | 1917 | -1940 | Biarritz + |
| | Olsen, Bjarne Nikolai Øen, Merchant Navy | 1901 | -1940 | Eika + |
| | Olsen, Engebret, Merchant Navy | 1915 | -1940 | Eika + |
| | Olsen, Sigvart, Merchant Navy | 1903 | -1940 | Eika + |
| | Olsen, Oluf Martin, Merchant Navy | 1889 | -1940 | Start + |
| | Olsen, Henry Alfred, Merchant Navy | 1885 | -1940 | Hop + |
| | Olsen, Harald Nikolai, Merchant Navy | 1912 | -1940 | Steinstad + |
| | Olsen, Sven Guttorm, Merchant Navy | 1886 | -1940 | Steinstad + |
| | Olsen, Trygve, Merchant Navy | 1922 | -1940 | Steinstad + |
| | Olsen, Olaf Johan, Merchant Navy | 1910 | -1941 | Vespasian + |
| | Olsen, Thorbjørn, Merchant Navy | 1917 | -1941 | Vespasian + |
| | Olsen, John Eugen, Merchant Navy | 1890 | -1941 | Benjamin Franklin + |
| | Olsen, Thage, Merchant Navy | | -1941 | Benjamin Franklin + |
| | Olsen, Hjalmar, Merchant Navy | 1905 | -1941 | Svein Jarl + |
| | Olsen, Karl, Merchant Navy | 1910 | -1941 | Augvald + |
| | Olsen, Ole Ludvig, Merchant Navy | 1921 | -1941 | Augvald + |
| | Olsen, Einar Jørgen Kr., Merchant Navy | 1917 | -1941 | Murjek + |
| | Olsen, Thorleif, Merchant Navy | | | Beduin |
| | Olsen, Alexander, Merchant Navy | | -1941 | Hørda + |
| | Olsen, Trygve, Merchant Navy | 1916 | | Nyholt |
| | Olsen, Ole Peder, Merchant Navy | 1893 | -1942 | Sarita, Octavian + |
| | Olsen, Søren, Merchant Navy | 1924 | | Alexandra Høegh |
| | Olsen, Ludvig Gerhard L., Merchant Navy | 1902 | -1942 | Belize + |
| | Olsen, Sverre Andreas, Merchant Navy | 1892 | -1965 | Terje Viken, Anna Knudsen |
| | Olsen, Henry, Merchant Navy | 1892 | -1942 | William Hansen + |
| | Olsen, Odd, Merchant Navy | 1914 | | Leiesten |
| | Olsen, John Olaf, Merchant Navy | 1905 | -1942 | Ringstad + |
| | Olsen, Oskar Sjuls, Merchant Navy | 1890 | | Ringstad |
| | Olsen, Andreas, Merchant Marine | 1891 | -1942 | Ramapo + |
| | Olsen, Edvin Racin, Merchant Navy | 1917 | | Sama |
| | Olsen, Olav Martin, Merchant Navy | | | Sama |
| | Olsen, Ragnvald Høyerdal, Merchant Navy | 1921 | -1942 | Sama + |
| | Olsen, Thorleif, Merchant Navy | | | Sama |
| | Olsen, Godske, Merchant Navy | 1898 | -1969 | Risanger, Eidanger |
| | Olsen, Tor, Merchant Navy | | | Eidanger |
| | Olsen, Alexander, Merchant Navy | 1886 | -1942 | Finnanger + |
| | Olsen, Birger Eugen, Merchant Navy | 1919 | -1942 | Finnanger + |
| | Olsen, Reidar, Merchant Navy | 1919 | -1942 | Finnanger + |
| | Olsen, Nils, Merchant Navy | 1917 | | O.A. Knudsen |
| | Olsen, Olaf, Merchant Navy | 1896 | | Sydhav |
| | Olsen, Sverre Bernhard, Merchant Navy | 1913 | -1950 | Sydhav |
| | Olsen, Harry Goodwin, Merchant Navy | 1914 | | Hvoslef |
| | Olsen, Svend Aage, Merchant Navy | 1920 | | Hvoslef |
| | Olsen, Johan Christian, Merchant Navy | 1906 | -1942 | Ingerto + |
| | Olsen, Ole, Merchant Marine | 1917 | -1942 | Ceiba + |
| | Olsen, Thormod, Merchant Navy | 1910 | -1943 | Vestfold + |
| | Olsen, Harald, Merchant Navy | | | Kollbjørg |
| | Olsen, Bjarne Fr., Merchant Navy | 1908 | -1943 | Nortind + |
| | Olsen, Eilert, Merchant Navy | | | Glittre |
| | Olsen, James Patrick, Merchant Navy | 1910 | -1943 | Empire Tower + |
| | Olsen, Knut M., Merchant Navy | | | Thorstrand |
| | Olsen, Olaf Bertrand, Merchant Navy | 1904 | -1943 | Thorstrand + |
| | Olsen, Olav, Merchant Navy | 1907 | -1943 | Thorstrand + |
| | Olsen, Olav, Merchant Navy | | | Thorstrand |
| | Olsen, Olaf, Merchant Navy | | | Jamaica |
| | Olsen, Olav, Merchant Navy | | | Jamaica |
| | Olsen, Thorbjørn, Merchant Navy | | | Jamaica |
| | Olsen, Alfred Harry Thorle, Merchant Navy | 1913 | -1943 | Bonneville + |
| | Olsen, Ove Bernard, Merchant Navy | | | Tabor |
| | Olsen, Ferdinand Eugen, Merchant Navy | 1904 | -1943 | Brant County + |
| | Olsen, Thorbjørn, Merchant Navy | | | Brant County |
| | Olsen, Ole, Merchant Navy | | | Viva |
| | Olsen, Kåre, Merchant Navy | | | Fenris |
| | Olsen, Olav, Merchant Navy | | | Fenris |
| | Olsen, Ole K., Merchant Navy | | | Fenris |
| | Olsen, Thoralf, Merchant Navy | | | Fenris |
| | Olsen, Sven, Merchant Navy | | | Erling Brøvig |
| | Olsen, Bjarne, Merchant Navy | 1918 | -1945 | Polarland + |
| | Olsen, Fridtjof, Merchant Navy | | | Solør |
| | Olsen, A.L., Royal Norwegian Navy | | -1945 | HNoMS Nordhav II (FY 1906) + |
| | Olsen, H., Merchant Navy | | | Tosca |
| | Olsen, O., Merchant Navy | | | Tosca |
| | Olsen, Kaare Arthur, Merchant Navy | | | Helle |
| | Olsen, Kristian, Merchant Navy | | | Lincoln Ellsworth |
| | Olsen, Olav, Merchant Navy | | | Lincoln Ellsworth |
| | Olsen, Gunerius, Merchant Navy | 1886 | -1941 | Polyana + |
| | Olsen, Alf J., Merchant Navy | 1906 | -1941 | Rimfakse + |
| | Olsen, Oscar Baldemar, Merchant Navy | 1916 | -1941 | Rimfakse + |
| | Olsen, Hans Antoni, Merchant Navy | 1913 | | Caledonia, Koll |
| | Olsen, Knut Olav, Merchant Navy | 1919 | -1941 | John P. Pedersen + |
| | Olsen, Odd Rønning, Merchant Navy | | | Rinda |
| | Olsen, Ragnar Asbjørn, Merchant Navy | 1906 | -1941 | Rinda + |
| | Olsen, Andreas Feirås, Merchant Navy | 1921 | | Koll |
| | Olsen, Magnus Odmar, Merchant Navy | 1902 | -1983 | Koll |
| | Olsen, Dan, Merchant Navy | | | Kollskegg |
| | Olsen, Håkon Aashildrød, Merchant Navy | 1915 | | Kollskegg |
| | Olsen, Ole Lindemann, Merchant Navy | | | Kollskegg |
| | Olsen, Reidar Garder, Merchant Navy | 1893 | -1972 | Kollskegg |
| | Olsen, John Georg, Merchant Navy | 1908 | | Lancing |
| | Olsen, Olav, Merchant Navy | 1904 | | Lancing |
| | Olsen, Thomas Andreas Smedsvig, Merchant Navy | 1905 | -1976 | Lancing |
| | Olsen, Fredrik Anton, Merchant Navy | 1917 | -1942 | Chr. Knudsen + |
| | Olsen, Johannes, Merchant Navy | 1895 | -1942 | Chr. Knudsen + |
| | Olsen, Valdemar Laurin, Merchant Navy | 1913 | -1942 | Chr. Knudsen + |
| | Olsen, Rolf, Merchant Navy | | | Grenanger |
| | Olsen, Einar, Merchant Navy | | | Bris |
| | Olsen, Ole Edvard, Merchant Navy | 1896 | -1942 | Taborfjell + |
| | Olsen, Trygve, Merchant Navy | | | Bidevind |
| | Olsen, Nils T., Merchant Navy | | | Skottland |
| | Olsen, Bernt, Merchant Navy | 1896 | | Beth |
| | Olsen, Håkon Vold, Merchant Navy | 1923 | | Beth |
| | Olsen, Frithjof, Merchant Navy | | | Hamlet |
| | Olsen, Arne, Merchant Navy | 1896 | | Lysefjord |
| | Olsen, Anker, Merchant Navy | | | Scebeli |
| | Olsen, Olaf Nicolai, Merchant Navy | 1897 | -1943 | Scebeli + |
| | Olsen, Samuel, Merchant Marine | 1904 | | Samuel Jordan Kirkwood |
| | Olsen, Sigurd, Merchant Navy | | | Grado |
| | Olsen, Andreas Evald, Merchant Navy | 1902 | -1943 | Brand + |
| | Olsen, Ole T., Merchant Navy | | | Brand |
| | Olsen, Torbjørn Ness, Merchant Navy | | | Brand |
| | Olsen, Wilhelm Johannes, Merchant Navy | 1917 | -1943 | Sandanger + |
| | Olsen, Olaf, Merchant Navy | | | Storaas |
| | Olsen, Olaf, Merchant Navy | | | Storaas |
| | Olsen, Sven Rasin, Merchant Navy | | | Storaas |
| | Olsen, Karl, Merchant Navy | 1884 | -1943 | Hopetarn + |
| | Olsen, Arvid, Merchant Navy | | | Sneland I |
| | Olsen, Trygve, Merchant Navy | | | Sneland I |
| | Olsen, Gert Rene Conrad, Merchant Navy | 1923 | -1941 | Susan Mærsk + |
| | Olsen, Aage Rudolf, Merchant Marine | 1894 | -1942 | Azalea City + |
| | Olsen, Knud Edmund, Merchant Navy | 1910 | -1939 | Scotia + |
| | Olsen, Anker Stjerne Adolf, Merchant Navy | 1898 | -1939 | Magnus + |
| | Olsen, Lauritz, Merchant Navy | 1887 | -1939 | Magnus + |
| | Olsen, Elieser Martin, Merchant Navy | 1906 | -1940 | Bothal + |
| | Olsen, Arthur, Merchant Navy | 1921 | -1940 | Viking + |
| | Olsen, Lars, Merchant Navy | | -1942 | Hans Egede + |
| | Olsen, Oscar, Merchant Navy | | | San Alvaro |
| | Olsen, Martin, Merchant Marine | 1922 | | Sylvan Arrow, Crijnssen |
| | Olsen, Lawrence, Merchant Marine | | -1942 | Swiftsure, Zaandam + |
| | Olsen, Arthur Christian, Merchant Navy | 1903 | | Andrea Brøvig, Robert E. Lee |
| | Olsen, Fritz, Merchant Marine | 1912 | | Hanseat |
| | Olsen, Kristian, Merchant Navy | 1900 | | Frontenac |
| | Olsen, Ralph Warren, USNR | | | USS Block Island (CVE 21) |
| | Olsen, Herman Nickolai, Merchant Marine | 1890 | -1942 | James McKay + |
| | Olsen, Matello Norby, Merchant Marine | 1892 | -1958 | Cripple Creek |
| | Olsen, Joseph W., Civilian | | | Dorchester + |
| | Olsen, Ivar Arnold, Merchant Navy | 1919 | | Kongsgaard |
| | Olsen, Oskar, Merchant Marine | 1905 | | Penelope |
| | Olson, Leif Martin, Merchant Marine | | -1942 | Caddo + |
| | Olson, Eino Joseph, Merchant Marine | | -1943 | Hastings + |
| | Olson, Kenneth F., Merchant Marine | | -1943 | Robert Gray + |
| | Olson, Edward Elmer, USNR | | -1943 | Charles C. Pinckney + |
| | Olson, James William, USNR | | -1943 | USS Buck (DD 420) + |
| | Olson, O.H.S., Merchant Navy | 1908 | | Hammaren |
| | Olson, Svend, Merchant Navy | | -1942 | Senta + |
| | Olson, Herbert Vidrian, Merchant Marine | | | James K. Polk |
| | Olson, Theodore Wallin, USNR | | | USS Bristol (DD 453) |
| | Olson, Lester L., Merchant Marine | 1925 | | Seakay |
| | Olson, Oscar Frederick, USNR | | | USS Block Island (CVE 21) |
| | Olson, Harry, Merchant Navy | 1918 | | Wilja |
| | Olson, Peter W., Merchant Marine | | | J.A. Mowinckel |
| | Olson, William, Merchant Marine | 1897 | | Catahoula |
| | Olsowy, Raymond Cecil, USNR | | | USS LST-333 |
| | Olsrød, Lars Kristian, Merchant Navy | 1902 | -1974 | Maloja |
| | Olsson, Anders P., Merchant Marine | | -1943 | Edward B. Dudley + |
| | Olsson, John Godfrid, Merchant Navy | | | Calabria |
| | Olsson, F., Merchant Navy | | | Industria |
| | Olsson, Anton Nicolaus, Merchant Navy | | -1945 | Magne + |
| | Olsson, Charles Gunnar William, Merchant Navy | 1903 | -1940 | British General + |
| | Olsson, John Bertil, Merchant Navy | 1922 | | Besholt |
| | Olsson, Gunnar, Merchant Navy | | -1941 | Hørda + |
| | Olsson, Gustav, Merchant Navy | 1898 | -1975 | Lancing, N.T. Nielsen-Alonso |
| | Olsson, Alfred Verner, Merchant Navy | 1882 | -1940 | Daphne + |
| | Olsson, Oscar Rickard, Merchant Navy | 1881 | -1942 | Yngaren + |
| | Olsson, Svante, Merchant Marine | | -1943 | Winkler + |
| | Olsson, Birger Wallentin, Merchant Navy | 1901 | -1940 | Sylvia + |
| | Olsson, Gustav Ragnar, Merchant Navy | 1901 | -1940 | Sylvia + |
| | Olsson, Oskar Vitalis, Merchant Navy | 1886 | -1940 | Flandria + |
| | Olsson, Arvid L., Merchant Navy | 1899 | -1940 | Liana + |
| | Olsson, B.Th., Merchant Navy | | | Liana |
| | Olsson, Karl Oskar, Merchant Navy | | -1940 | Santos + |
| | Olsson, Ivan Kasimir, Merchant Navy | 1885 | -1940 | Canton + |
| | Olsson, Fritz Malte, Merchant Navy | 1900 | -1940 | Stureholm + |
| | Olsson, Marta Regina, Civilian | | -1941 | Venezuela + |
| | Olsson, Werner, Merchant Navy | 1890 | -1941 | Rothermere + |
| | Olsvik, Edvard Jon, Merchant Navy | | -1941 | Erviken + |
| | Olsvik, Otto, Merchant Navy | | | Hindanger |
| | Olszanski, Andrzej, Polish Navy | | -1943 | ORP Orkan + |
| | Olszewski, John B., Merchant Marine | | -1943 | Robert Gray + |
| | Olszewski, Joseph Stanley, USCG | | -1943 | Dorchester + |
| | Olthoff, Johannes Willem, Merchant Navy | 1901 | | Telamon |
| | Oltremonti, Giovanni, Civilian | | -1942 | Nova Scotia + |
| | Olufsen, Svend Aage, Merchant Marine | | -1943 | West Portal + |
| | Oluwole, Frank, Merchant Navy | 1914 | | Belgian Soldier |
| | Olver, Jack Alfred William, FAA | 1921 | -1941 | Almeda Star + |
| | Olyslaegers, Georges, Merchant Navy | | | Gand |
| | Oman, Alexander, Merchant Navy | | | San Gaspar |
| | Omar Ahmed Ibrahim, , Merchant Navy | 1917 | -1940 | Cree + |
| | Omar Warsama Deir, , Merchant Navy | 1911 | -1944 | King Frederick + |
| | Omatayo, John, Merchant Navy | 1918 | -1941 | Seaforth + |
| | Ombellini, Luigi, Regio Esercito | 1917 | -1942 | Laconia + |
| | Omda Mian, , Merchant Navy | | -1943 | City of Pretoria + |
| | Omholt, Alf, Merchant Navy | | | Astrell |
| | Omholt, Andreas, Merchant Navy | | | Minister Wedel |
| | Omland, Sverre, Merchant Navy | 1920 | | Andrea Brøvig, Robert E. Lee |
| | Ommering, Arie, Merchant Navy | 1918 | | Leto |
| | Ommundsen, Osvald, Merchant Navy | 1917 | | Anna Knudsen |
| | Omogoye, Jacob, Civilian | 1918 | -1943 | Phemius + |
| | Omohundro, Charles, Merchant Marine | | | James W. Denver |
| | Omsland, Odd Martinius, Merchant Navy | 1911 | -1973 | Lancing |
| | On Leng Wan, , Merchant Navy | 1895 | -1942 | Otina + |
| | Onda, Steven, USNR | | | USS Barr (DE 576) |
| | Onelli, Mario, Regio Esercito | 1916 | -1942 | Laconia + |
| | Oneta, Osvino, Civilian | | -1942 | Nova Scotia + |
| | Ong Ah Kun, , Merchant Navy | | -1941 | Calchas + |
| | Ong Ah Nghee, , Merchant Navy | | | Henrik |
| | Ong Ah Tiew, , Merchant Navy | | -1943 | Corbis + |
| | Ong Sing Ching, , Merchant Navy | 1918 | -1940 | Pyrrhus + |
| | Ong Zoen Ching, , Merchant Navy | | -1941 | Calchas |
| | Ong-Dek Kim, , Merchant Navy | | | Beduin |
| | Onghena, Joseph, Merchant Navy | 1901 | | Indier |
| | Onloghas, Constantine, Merchant Navy | | -1942 | Koumoundouros + |
| | Onofaye, Gabriel Tolorunzu Ozolekorakorobiade, Merchant Navy | 1906 | -1942 | Tacoma Star + |
| | Onofrillo, Pasquale, Regio Esercito | 1916 | -1942 | Laconia + |
| | Onoja, J.A., Merchant Navy | | -1942 | Rio Blanco + |
| | Onselen, L.L. van, Royal Dutch Navy | | | Colombia |
| | Onsoe, B., Royal Dutch Navy | | | Colombia |
| | Onstott, , USNR | | | Cities Service Missouri |
| | Onyekwere, Festus, Civilian | 1913 | -1943 | Phemius + |
| | Onyeson, Joseph, Merchant Navy | 1912 | -1940 | Accra + |
| | Onzols, Petris, Merchant Navy | | -1945 | Corvus + |
| | Ooijman, Johannes, Merchant Navy | 1917 | | Soekaboemi |
| | Oomen, Leonardus C., Merchant Navy | | | Pacific |
| | Oomer Ali Soolchand Rajini, , Merchant Navy | | | Marit |
| | Oomkes, Gerardus Nicolaas, Merchant Navy | 1894 | | Dempo |
| | Oorde, Hendrik Anthonius van, Royal Dutch Navy | 1911 | | Colombia |
| | Oorschot, G. van, Merchant Navy | | | Suriname |
| | Oort, Roelof van, Merchant Navy | 1914 | | Moordrecht |
| | Oosman Fackeer, , Merchant Navy | | | Kota Tjandi |
| | Oost, Geert Johannes Jan, Merchant Navy | 1906 | | Boekelo |
| | Oosten, Theodorus Marie Johannes van, Merchant Navy | 1915 | -1945 | Pacific + |
| | Oosten, Kornelis van, Merchant Navy | 1906 | | Amsterdam |
| | Oostende, Marinus Hendricus van, Merchant Navy | 1903 | -1940 | Moordrecht + |
| | Oostendorp, Henry van, Merchant Navy | 1923 | | Gaasterkerk |
| | Oosterbaan, Nicolaas, Merchant Navy | 1897 | | Jagersfontein |
| | Oosterhout, Johannes Bastiaan van, Merchant Navy | 1915 | | Spar, Alderamin |
| | Oosterhout, Johannes van, Merchant Navy | 1916 | | Soekaboemi |
| | Oosterlinck, Karel, Merchant Navy | | -1942 | Emile Francqui + |
| | Oosterom, Cornelis Johannes, Royal Dutch Navy | 1920 | -1942 | HNMS Isaac Sweers (G 83) + |
| | Oosterveer, Antoon, Merchant Navy | 1922 | -1940 | Haulerwijk + |
| | Oosterveld, Hendrik Jan, Royal Dutch Navy | 1917 | -1942 | HNMS Isaac Sweers (G 83) + |
| | Oosthoek, Nicolaas, Merchant Navy | 1922 | -1942 | Tjileboet + |
| | Oosthuizen, J.J., South African Army | 1912 | -1942 | Nova Scotia + |
| | Oostrom, Cornelis, Merchant Navy | 1915 | -1942 | Hobbema + |
| | Ooststroom, Adriaan van, Merchant Navy | 1895 | | Winterswijk |
| | Ootjers, T., Merchant Navy | | | Tajandoen |
| | Oow Foo, , Merchant Navy | | | Hav |
| | Opdahl, Sigurd K., Merchant Navy | | | Triton |
| | Opdahl, Sigurd, Merchant Navy | | | Oregon Express |
| | Opdahl, Sigurd, Merchant Navy | | | Stigstad |
| | Opdal, Olaf, Merchant Navy | | -1940 | Stureholm + |
| | Opdebeek, Louis, Merchant Navy | | -1941 | Ville de Liège + |
| | Openshaw, Percy Godfrey, RN | 1913 | -1944 | HMS Penelope (97) + |
| | Operti, Egidio Ferrucio, Civilian | 1890 | -1940 | Arandora Star + |
| | Opheim, Jostein Oddvar, Merchant Navy | 1920 | -1941 | Ringhorn + |
| | Opheim, Martin Andreasen, Merchant Navy | 1914 | -1941 | Ringhorn + |
| | Opheim, Asbjørn, Merchant Navy | 1917 | | Frontenac |
| | Opiat, Wladyslaw, Polish Navy | | -1943 | ORP Orkan + |
| | Opie, Frank, Merchant Navy | 1925 | -1942 | Stornest + |
| | Opie, Charles, RN | 1911 | -1943 | Clarissa Radcliffe + |
| | Oppen, Levinus Petrus van, Merchant Navy | 1921 | | Mijdrecht |
| | Oppenheimer, Edward, Merchant Marine | | -1942 | Cities Service Toledo + |
| | Oppenheimer, Morton, US Army | | -1943 | Dorchester + |
| | Oprey, Henry John, Merchant Navy | 1892 | -1940 | Diplomat + |
| | Opsal, Oskar Sigvald, Merchant Navy | 1915 | -1942 | Bennestvet + |
| | Opsal, Borgner, Merchant Navy | | | Gundersen |
| | Opstad, Hjalmar, Merchant Navy | | | Tudor |
| | Opyr, Walter, Merchant Marine | | -1943 | Edward B. Dudley + |
| | Opyrchaski, Edward, Merchant Marine | 1898 | -1942 | Olympic + |
| | Oram, Roy, RN | 1923 | -1944 | HMS Penelope (97) + |
| | Oram, Reginald Philip, RAN | 1896 | -1941 | HMAS Parramatta (L 44) + |
| | Oram, George James, Merchant Navy | 1888 | -1941 | Pacific + |
| | Oram, Jack Edward, RAFVR | 1919 | -1941 | Anselm + |
| | Oram, William Henry, Merchant Marine | 1901 | -1942 | Barbara + |
| | Oramas, José Lino, Merchant Navy | 1909 | -1943 | Bonneville + |
| | Orandi, Hillar, Merchant Navy | 1906 | | Egda |
| | Orange, Harold J., USN | | -1941 | USS Reuben James (DD 245) + |
| | Oranje, Adrianus C., Merchant Navy | 1919 | | Rotterdam |
| | Orasto, Piedado, Merchant Navy | | -1943 | Sembilangan + |
| | Oravs, Janis, Merchant Navy | 1906 | | Everagra |
| | Orb, Henry F., USNR | | -1943 | Henry R. Mallory + |
| | Orbase, Canuto Ola, Merchant Marine | 1898 | -1942 | Raphael Semmes + |
| | Orchard, Albert Frederick Charles, RN | 1915 | -1941 | HMS Galatea (71) + |
| | Orchard, Kenneth Russell, RN | 1916 | -1941 | HMS Galatea (71) + |
| | Orchard, Arthur John, RN | 1923 | -1944 | HMS Tweed (K 250) + |
| | Orchard, I., RN | | | Indra |
| | Orchard, , RN | | | Darina |
| | Orchard, Frank, Merchant Navy | | | Sithonia |
| | Orchel, John, USN | | | USS Block Island (CVE 21) |
| | Orchison, Charles Watson Begg, RN | 1923 | -1943 | HMS Itchen (K 227) + |
| | Ord, Thomas Foster, RN | 1915 | -1942 | HMS Fidelity (D 57) + |
| | Ord, John Hamilton, Civilian | 1941 | -1943 | Canadian Star + |
| | Ord, John Lionel, British Army | 1906 | -1943 | Canadian Star + |
| | Ord, Lesley Maud Hamilton, Civilian | 1907 | -1943 | Canadian Star + |
| | Orde, Anne Winifred, Civilian | | | Andalucia Star |
| | Orde, Allen, Merchant Navy | 1918 | -1941 | Empire Heron + |
| | Oren, Clifford J., US Army | | -1943 | Dorchester + |
| | Orfanidis, Pantelis, Merchant Navy | 1914 | | Pantelis |
| | Orford, Frederick Peter, RN | | -1944 | HMS Laforey (G 99) + |
| | Orford, Thomas, Merchant Navy | | | Amakura |
| | Organ, George, NAAFI | 1923 | -1941 | HMS Galatea (71) + |
| | Organ, Martin, Merchant Navy | 1900 | -1942 | Rosenborg + |
| | Organ, Ellis Arthur, Merchant Navy | 1911 | -1941 | Black Osprey + |
| | Orger, Charles W., Merchant Navy | 1905 | -1941 | Almeda Star + |
| | Orges, Richard H., RM | | | HMS Royal Oak (08) |
| | Orholt, Per, Merchant Navy | 1919 | -1941 | Hørda + |
| | Oribelli, Primo, Regio Esercito | 1919 | -1942 | Laconia + |
| | Oribine, David, RCNVR | 1921 | -1942 | Ettrick + |
| | Orieux, Julien Paul Francis, Free French Navy | 1920 | -1942 | Président Doumer + |
| | Orillo, Fernando, Merchant Navy | | | Ante Matkovic |
| | Orin, Solano Samonte, USNR | | | USS Block Island (CVE 21) |
| | Orkpaban, Bernard, Merchant Navy | 1915 | | Stad Amsterdam |
| | Orlandi, Francesco, Regio Esercito | 1914 | -1942 | Laconia + |
| | Orlandi, Renato, Regio Esercito | 1921 | -1942 | Laconia + |
| | Orlando, Sam, Merchant Marine | 1919 | | Ben and Josephine |
| | Orlando, Umberto, Regio Esercito | 1910 | -1942 | Laconia + |
| | Orley, Edward Claude, RN | 1919 | -1941 | HMS Gladiolus (K 34) + |
| | Orloff, Edward A., USNR | | -1943 | Edward B. Dudley + |
| | Orlomoski, William E., US Army | 1917 | -1943 | Dorchester + |
| | Orman, George, Merchant Navy | | | Andalucia Star |
| | Orman, G., Merchant Navy | 1908 | | Arandora Star |
| | Orme, William Leslie, RCNVR | 1922 | -1944 | HMCS Valleyfield (K 329) + |
| | Orme, George William, RN | | -1942 | HMS Matabele (G 26) + |
| | Ormerod, Frank, RN | | -1942 | HMS Belmont (H 46) + |
| | Ormes, William George, British Army | | -1942 | Scottish Chief + |
| | Ormestad, Johan Arnt, Merchant Navy | 1916 | | South Africa |
| | Ormod, Frederick J., Merchant Navy | | | Melrose Abbey |
| | Ormsby, Edward John, RNR | | -1940 | HMS Cape Howe (X 02) + |
| | Ormston, Andrew, Merchant Navy | 1904 | -1940 | British Premier + |
| | Ornaghi, Mario, Regio Esercito | 1917 | -1942 | Laconia + |
| | Orndorff, Henry Russell, Merchant Marine | 1923 | -2016 | James B. Stephens |
| | Orpin, Frank Enoch, Merchant Navy | 1902 | -1940 | Matina + |
| | Orpwood, Leslie Herbert, RN | 1917 | -1941 | HMS Barham (04) + |
| | Orr, Harry James, RFR | 1901 | -1942 | HMS Avenger (D 14) + |
| | Orr, David, RN | | -1942 | HMS Farouk + |
| | Orr, Ralph, RN | | -1945 | HMS Lapwing (U 62) + |
| | Orr, Edward, Merchant Navy | 1902 | -1942 | Abosso + |
| | Orr, John, Merchant Navy | 1893 | -1941 | Lapwing + |
| | Orr, Peter, Merchant Navy | 1893 | -1940 | Empire Statesman + |
| | Orr, William, Merchant Navy | 1900 | -1941 | Shuntien + |
| | Orr, George Fulton, Merchant Navy | 1923 | -1942 | Warwick Castle + |
| | Orr, Nelson Joseph, Merchant Navy | 1907 | -1942 | Induna + |
| | Orr, Donald Alexander, Merchant Navy | | | Strathallan |
| | Orr, D., British Army | | | Darina |
| | Orr, Thomas, RN | | | HMS Courageous (50) |
| | Orr, J.W., Civilian | 1916 | | City of Simla |
| | Orr, Grant Gordon, USN | 1925 | -1968 | Hahira |
| | Orrah, William, RN | 1917 | -1941 | HMS Gladiolus (K 34) + |
| | Orrell, Thomas, Merchant Navy | 1921 | | Empire Gem |
| | Orrick, Thomas Ismay, RN | 1925 | -1944 | HMS Penelope (97) + |
| | Orrum, George, Merchant Navy | | | Empire Sun |
| | Orsborn, John Arthur, RN | 1920 | -1942 | HMS Grove (L 77) + |
| | Orsborn, David Charles, RN | 1923 | | HMS Marne (G 35) |
| | Orseth, Kåre Messel, Merchant Navy | 1900 | -1942 | Finnanger + |
| | Orsi, Giuseppe, Civilian | 1890 | -1940 | Arandora Star + |
| | Orsi, Pietro, Civilian | 1888 | -1940 | Arandora Star + |
| | Orsini, Albert, USNR | | | USS Block Island (CVE 21) |
| | Orsini, Edoardo, Regio Esercito | 1921 | -1942 | Laconia + |
| | Ortega, Joe B., US Army | | -1944 | Leopoldville + |
| | Ortega, G., Merchant Navy | | | Draco |
| | Ortega Flores, Guillermo, Merchant Navy | 1911 | -1942 | Tolten + |
| | Ortegat, Jacques, Merchant Navy | | -1942 | Emile Francqui + |
| | Ortensio, Francesco, Merchant Navy | | -1942 | Nova Scotia + |
| | Ortic, Angeul, Merchant Marine | | | Jack |
| | Ortica, Angelo, Regio Esercito | 1917 | -1942 | Laconia + |
| | Ortis, Giacomo, Regio Esercito | 1920 | -1942 | Laconia + |
| | Ortiz, Victor, Merchant Marine | | -1942 | Lemuel Burrows + |
| | Ortiz, J.C., Civilian | | -1941 | Empire Stream + |
| | Ortiz, Telesforo M., Merchant Marine | | | Lammot Du Pont |
| | Ortiz, Alfredo, Merchant Marine | 1918 | | Ceiba |
| | Ortizuela, Pedro, USN | | -1941 | USS Reuben James (DD 245) + |
| | Ortleb, Otto Karl, Merchant Marine | 1901 | -1942 | Otho + |
| | Ortlip, Donald Albert Frederick, USNR | | | USS Frederick C. Davis (DE 136) |
| | Ortolani, Settimio, Regio Esercito | 1919 | -1942 | Laconia + |
| | Orton, Richard, Merchant Navy | 1904 | -1940 | Eston + |
| | Orton, Stuart Draycott, RN | 1911 | -1944 | HMS Penelope (97) + |
| | Orton, John William, RN | 1923 | -1942 | HMS Culver (Y 87) + |
| | Ortt, Felix Dono, Merchant Navy | 1907 | | Soesterberg |
| | Orud, Oscar, Merchant Navy | | | Nortind |
| | Orud, Oskar, Merchant Navy | | | Eastern Star |
| | Orula, Leo, Merchant Navy | 1923 | -1942 | William Hansen + |
| | Orvin, Charles Peter, RN | 1899 | -1941 | Nerissa + |
| | Os, Cornelis Leendert van, Merchant Navy | 1885 | | Alderamin |
| | Osa, N., Merchant Navy | | | Tosca |
| | Osanie, , Merchant Navy | | | Soekaboemi |
| | Osban, Leroy, Merchant Marine | 1917 | -1987 | Esso Nashville, Paul H. Harwood |
| | Osberg, Gunder, | | | Thorstrand |
| | Osbon, Albert, Merchant Navy | 1882 | -1940 | Sulaco + |
| | Osborn, Robert Leonard, Merchant Navy | 1913 | -1939 | Navasota + |
| | Osborne, Richard D., Merchant Marine | | -1943 | Samuel Heintzelman + |
| | Osborne, Robert James, RCNVR | 1919 | -1943 | HMCS St. Croix (I 81) + |
| | Osborne, Thomas George, RN | 1920 | -1939 | HMS Royal Oak (08) + |
| | Osborne, Frank, RN | 1917 | -1941 | HMS Barham (04) + |
| | Osborne, Frederick, RN | | -1943 | HMS Welshman (M 84) + |
| | Osborne, Harry, RN | 1923 | -1943 | HMS Birmingham (19) + |
| | Osborne, Robert William, RN | 1912 | -1943 | HMS Puckeridge (L 108) + |
| | Osborne, Ernest James, RN | 1915 | -1942 | HMS Veteran (D 72) + |
| | Osborne, Ralph Robert, RN | 1920 | -1942 | HMS Veteran (D 72) + |
| | Osborne, William John, RNPS | 1915 | -1942 | HMS Laertes (T 137) + |
| | Osborne, Frederick Albert, RN | 1920 | -1945 | HMS Goodall (K 479) + |
| | Osborne, John Kermit, USNR | | -1943 | Puerto Rican + |
| | Osborne, Fred Laurence, Merchant Navy | 1913 | -1941 | Empire Heron + |
| | Osborne, William Percy, Merchant Navy | 1900 | -1941 | Lapwing + |
| | Osborne, Alfred James, Merchant Navy | 1920 | -1940 | Matina + |
| | Osborne, George William Guy, Merchant Navy | 1918 | -1942 | Opawa + |
| | Osborne, Thomas Edward, RN | | | Earlston |
| | Osborne, Norman Frederick, Fishing Fleet | 1922 | -1941 | Commander Horton + |
| | Osborne, Lionel Alfred, Merchant Navy | | | Llanover |
| | Osborne, A.G., Merchant Navy | | | Empire Stanley |
| | Osborne, William Algerine, USN | | | USS Gannet (AVP 8) |
| | Osborne, Arthur Stanley, British Army | 1916 | -1942 | Empire Sky + |
| | Osborne, Samuel, Merchant Navy | 1911 | | Peterton |
| | Osborne, P., Merchant Navy | | | Breedijk |
| | Osborne, James Alton, USN | | | USS Kearny (DD 432) |
| | Osborne, George L.S., Merchant Marine | 1913 | | Seakay |
| | Osborne, Jr., John Francis, USNR | | | USS Block Island (CVE 21) |
| | Osburn, Arthur Robert, Merchant Navy | | | Palma |
| | Oscarsen, Per, Merchant Navy | | | Triton |
| | Oscarsson, Erik Johan Oscar, Merchant Navy | 1921 | | Castor |
| | Oscarsson, Arvid, Merchant Navy | | | Frank Seamans |
| | Oscurelli, Palmiro, Regio Esercito | 1912 | -1942 | Laconia + |
| | Ose, Olaf Wilford, Merchant Navy | 1919 | -1941 | Polyana + |
| | Osepa, Vincentius Paula, Merchant Navy | 1891 | | Flora |
| | Osi Mian, , Merchant Navy | 1912 | -1944 | Nairung + |
| | Osier, Leuign Winton, USCG | | -1942 | USS Muskeget (WAG 48) + |
| | Osinski, Zigmund W., Merchant Marine | | | J.A. Mowinckel |
| | Oskam, Egbert Corneles, Merchant Navy | 1913 | -1940 | Moordrecht + |
| | Oskam, Willem Marinus Jacobus, Merchant Navy | 1903 | | Stad Amsterdam |
| | Oskar, Aanensen, Merchant Navy | | | Monagas |
| | Oskarsen, Harry, Merchant Navy | | | Ruth I |
| | Oskarson, Karl Einar, Merchant Navy | | | New Sevilla |
|
| | Óskarsson, Jón, Fishing Fleet | 1918 | -1942 | Jon Olafsson + |
| | Óskarsson, Theódór, Fishing Fleet | 1918 | -1941 | Jarlinn + |
|
| | Oslen, Robert Frank, USN | | | USS Kearny (DD 432) |
| | Oslizlo, Teddy A., USNR | | -1943 | Edward B. Dudley + |
| | Osman, Ali bin, Merchant Navy | 1912 | -1940 | Whitford Point + |
| | Osman Ali, , Merchant Navy | | | Menin Ridge |
| | Osman Bakry Heiry, , Merchant Navy | 1904 | -1941 | Shuntien + |
| | Osman Cardi, , Merchant Navy | 1890 | -1940 | Lady Glanely + |
| | Osman Seqvalla, , Merchant Navy | | -1941 | Shuntien + |
| | Osmanis, Pereris Augustus, Merchant Navy | 1890 | -1942 | Adellen + |
| | Osmond, W., Merchant Navy | | -1942 | Kitty´s Brook + |
| | Osmundsen, Walter R., Merchant Navy | | | Stigstad |
| | Osmundsen, Walter, Merchant Navy | 1911 | | Lancing |
| | Osorio, Abel, Merchant Marine | | -1942 | Gulfoil + |
| | Oss, Johannes Theodorus van, Royal Dutch Army | 1910 | | Kota Tjandi |
| | Ossachuk, John, RCNVR | 1919 | -1944 | HMCS Shawinigan (K 136) + |
| | Osses Lara, Jesús Nazareno, Merchant Navy | 1896 | -1942 | Tolten + |
| | Ossler, Richard V., US Army | | | Jagersfontein |
| | Ossmow, John, Merchant Marine | 1902 | -1966 | Warrior |
| | Ostar Ali, , Merchant Navy | | -1943 | City of Pretoria + |
| | Ostar Mian, , Merchant Navy | 1899 | -1942 | Clan Macfadyen + |
| | Ostar Ullah, , Merchant Navy | 1910 | -1941 | City of Nagpur + |
| | Ostasiewski, Chester Stan, USNR | | -1942 | Gurney E. Newlin + |
| | Ostenmoroff, , Merchant Navy | | | Mendanau |
| | Osterbaurer, Mario, Regio Esercito | 1918 | -1942 | Laconia + |
| | Ostermiller, Herman Harold, USNR | | | USS Block Island (CVE 21) |
| | Osti, Giorgio, Regio Esercito | 1918 | -1942 | Laconia + |
| | Ostler, T.R., Canadian Army | | | Empire Sailor |
| | Ostojski, Stefan, Merchant Navy | | -1943 | Zagloba + |
| | Ostrich, Robert Eugene, USNR | 1925 | | USS Fiske (DE 143) |
| | Ostrom, Marvin C., Merchant Marine | | -1943 | Jonathan Sturges + |
| | Ostrow, Edgar J., US Army | | -1943 | Dorchester + |
| | Ostrowski, John, Merchant Marine | | -1942 | Louisiana + |
| | Ostvedt, Israel, Merchant Marine | | | Nicarao |
| | Ostyn, Jozef, Merchant Navy | | -1940 | Ville de Gand + |
| | Osu, Joseph, Merchant Navy | 1914 | -1941 | Adda + |
| | Osuldsen, Nils, Merchant Navy | | | Ferm |
| | Osval, P., Merchant Navy | | | Tosca |
| | Oswald, Joseph Henry, RN | 1898 | -1940 | Athelcrest + |
| | Oswald, George, Merchant Navy | 1924 | | Samsuva |
| | Otaki, Daisaburo, Merchant Navy | 1896 | -1940 | José de Larrinaga + |
| | Otero, Eduardo, Merchant Marine | | -1942 | L.J. Drake + |
| | Oteroma, Job, Merchant Navy | 1905 | -1942 | Oued Grou + |
| | Othen, Wilfred, Merchant Navy | 1910 | -1944 | Wayfarer + |
| | Othman Oner, , Merchant Navy | 1920 | | Marylyn |
| | Otis, Fred L., US Army | | -1944 | Leopoldville + |
| | Otozky, Stephen R., Merchant Marine | | -1943 | Jeremiah Van Rensselaer + |
| | Ott, Harry William, USCGR | | -1944 | USS Leopold (DE 319) + |
| | Ott, John M., Merchant Marine | 1915 | | Seakay |
| | Ott, Edwin Martin, USNR | 1925 | | USS Fiske (DE 143) |
| | Ottavi, Vincenzo, Civilian | | -1942 | Nova Scotia + |
| | Otten, Antonius, Royal Dutch Navy | 1920 | -1942 | HNMS Isaac Sweers (G 83) + |
| | Otten, Petrus Johannes, Merchant Navy | 1906 | | Colombia, Dempo |
| | Otten, Gijsbertus, Merchant Navy | 1908 | | Amstelland |
| | Ottencon, Victor, Merchant Navy | 1903 | -1941 | Anna Bulgaris + |
| | Ottensen, Victor A.B., Merchant Navy | | | Stargard |
| | Otter, Samuel Williams, USNR | | -1943 | Arthur Middleton + |
| | Otter, Leendert den, Merchant Navy | 1923 | | Volendam |
| | Otter, M.H. den, Merchant Navy | 1921 | | Volendam |
| | Otterbeck, Jørgen, Merchant Navy | | | Caledonia |
| | Otterbekk, Anders Jørgen, Merchant Navy | | -1943 | Hallfried + |
| | Otterberg, Olof Gunnar, Merchant Navy | 1919 | -1939 | Vistula + |
| | Otterlei, Ingebright, Merchant Navy | | | Vardaas |
| | Otterlei, Ingebrigt, Merchant Navy | | | Elin K. |
| | Otterloo, R.S., Royal Dutch Navy | | | Colombia |
| | Ottersen, Herbert Kristian, Merchant Navy | 1887 | -1942 | Sama + |
| | Ottersen, Kaare Egil Berg, Merchant Navy | 1908 | | Norness |
| | Otterskred, Markus J., Merchant Navy | 1909 | -1992 | Vestfold |
| | Otterson, Charles Harry, Merchant Navy | 1890 | -1943 | Jalabala + |
| | Ottesen, Øivind Dahl, Merchant Navy | 1917 | -1941 | Erviken + |
| | Ottesen, Anker Olai, Merchant Navy | 1912 | -1969 | Sørholt |
| | Ottesen, Kåre, Merchant Navy | | | Ferm |
| | Ottesen, Ragnvald Johan Didrik, Merchant Navy | 1892 | -1976 | Gunny |
| | Ottesen, Markus, Merchant Navy | | | Koll |
| | Ottevanger, Jacobus, Merchant Navy | 1881 | | Bilderdijk |
| | Ottley, Joseph, Fishing Fleet | 1904 | -1939 | Wigmore + |
| | Ottman, Friedrich, Merchant Navy | | -1939 | Agu + |
| | Otto, Harold Russel, Merchant Marine | | -1942 | James McKay + |
| | Otto, Albert Joseph, USN | 1922 | -1943 | USS Dorado (SS 248) + |
| | Otto, Valdimar Bertimus Laurits, Merchant Navy | 1887 | -1941 | San Florentino + |
| | Otto, Sjosdron, Merchant Navy | | | Langleeford |
| | Otto, Benjamin Francis, USNR | | | USS Fechteler (DE 157) |
| | Otto, Herbert Ross, USNR | | | USS Block Island (CVE 21) |
| | Ottolangui, George, Merchant Navy | 1921 | -1944 | Empire Heritage + |
| | Ottolini, Bernard Desmond, Merchant Navy | 1924 | -1941 | Jonathan Holt + |
| | Ottolini, Giovanni, Civilian | 1876 | -1940 | Arandora Star + |
| | Ottosen, Halfdan Møller, Merchant Navy | 1912 | | Amerikaland |
| | Ottowell, Joseph William, RN | 1920 | -1976 | HMS Bullen (K 469) |
| | Otway, James Herbert, Merchant Navy | 1922 | -1940 | Rotorua + |
| | Ou Fon, , Merchant Navy | 1916 | -1941 | Oilfield + |
| | Ouadah, Si-Ali, Merchant Navy | | -1942 | Roumanie + |
| | Ouamedo Savadogo, , Free French Army | 1917 | -1943 | Sidi-Bel-Abbès + |
| | Oudejans, Gerardus Antonius, Royal Dutch Army | 1909 | -1942 | Abosso + |
| | Ouden, Jacob den, Merchant Navy | 1903 | | Stad Amsterdam |
| | Ouden, J. van den, Royal Dutch Navy | | | Colombia |
| | Oudenaarden, Marinus Cornelis van, Merchant Navy | 1882 | | Bilderdijk |
| | Ouder, Lawrence Gamble, Merchant Marine | | -1942 | Nicarao + |
| | Ouderkerk, Pieter, Merchant Navy | 1907 | | Flensburg |
| | Oudeweetering, Theunis van de, Merchant Navy | 1908 | -1940 | Maas + |
| | Ouellet, Joseph Albert, Merchant Navy | 1916 | -1942 | Victolite + |
| | Ouellette, Armand Raymond, USN | | -1942 | USS Atik (AK 101) + |
| | Ouerenian Diarra, , Free French Army | 1917 | -1943 | Sidi-Bel-Abbès + |
| | Ouessa Poda, , Free French Army | 1919 | -1943 | Sidi-Bel-Abbès + |
| | Oughton, Thomas, RN | 1898 | -1939 | HMS Courageous (50) + |
| | Oughton, Kenneth Albert, RN | 1918 | -1941 | HMS Barham (04) + |
| | Ould, George, Merchant Marine | | | Delfina |
| | Oulianoff, Frank S., Merchant Marine | | -1942 | Jack + |
| | Oulton, Joseph, RN | 1916 | -1941 | St. Lindsay + |
| | Oultram, John Robinson, Merchant Navy | 1889 | -1942 | Abosso + |
| | Oumara Baldé, , Free French Army | 1921 | -1943 | Sidi-Bel-Abbès + |
| | Oumarou Amadou Kontago, , Free French Army | 1918 | -1943 | Sidi-Bel-Abbès + |
| | Ours, John J., USNR | | -1943 | Meriwether Lewis + |
| | Ours, J.J., USN | | | John Witherspoon |
| | Oursler, William C., Merchant Marine | 1889 | | Sama |
| | Ousmane Kébé, , Free French Army | 1919 | -1943 | Sidi-Bel-Abbès + |
| | Ousmane Sonko, , Free French Army | 1920 | -1943 | Sidi-Bel-Abbès + |
| | Oustorp, Ole Marton, Merchant Navy | | | Novasli |
| | Outen, G.J.N., Merchant Navy | | | Empire Stanley |
| | Outer, Dirk L. den, Merchant Navy | 1901 | | Volendam |
| | Outer, Gilles P. den, Merchant Navy | 1896 | | Volendam |
| | Outland, Earl Preston, USN | | | USS Buck (DD 420) |
| | Outlaw, George Reginald, RN | | -1941 | Almeda Star + |
| | Outlaw, Jesse Jacob, USCG | 1921 | -1962 | USCGC Alexander Hamilton (WPG 34) |
| | Outram, G.E., RN | | | Tibia |
| | Outred, Alfred Thomas, Merchant Navy | 1905 | -1942 | San Arcadio + |
| | Outred, Charles Edward, RN | 1911 | -1943 | Empire Lytton + |
| | Outten, Alvin G., US Army | | -1943 | Dorchester + |
| | Ouwenbroek, Pieter Adriaan, Merchant Navy | 1907 | | Alwaki |
| | Ouwerkerk, Leonardus Theodorus Marie, Merchant Navy | 1891 | | Mandalika |
| | Ouwerkerk, Karel Jacobus van, Merchant Navy | 1893 | | Jagersfontein |
| | Ouwerkerk, Mattheus Roelof van, Merchant Navy | 1907 | | Berhala |
| | Ove, Niels Henrik, Merchant Navy | 1915 | -1944 | Margit + |
| | Oven, James van, Merchant Navy | 1885 | | Jagersfontein |
| | Ovens, Joseph, RN | 1919 | -1942 | HMS Blean (L 47) + |
| | Ovens, James Paterson, Merchant Navy | 1907 | -1944 | Empire Lancer + |
| | Ovens, George, Merchant Navy | 1914 | -1942 | Empire Leopard + |
| | Ovenston, James McGill, Merchant Navy | | | Ferryhill |
| | Overbeek, Cornelis Gerardus van, Merchant Navy | 1918 | | Dempo |
| | Overbeke, III, Frank George, Merchant Marine | 1918 | -1999 | Mathew Luckenbach |
| | Overbury, William Henry, Merchant Navy | 1876 | -1941 | Stonepool + |
| | Overdick, Walter, Merchant Marine | 1910 | -1943 | Dorchester + |
| | Overend, William, RN | 1918 | -1940 | HMS Daring (H 16) + |
| | Overend, John, Merchant Navy | 1916 | | Zaanland |
| | Overheul, Leendert, Merchant Navy | 1899 | | Flensburg |
| | Overkleeft, Johannes, Merchant Navy | 1902 | | Stad Amsterdam |
| | Overland, Frederick John, RN | 1907 | -1942 | HMS Avenger (D 14) + |
| | Overly, Charles Frank, USNR | | -1943 | Thomas Ruffin + |
| | Overly, Roland Laverne, USNR | | -1944 | USS Fechteler (DE 157) + |
| | Overmark, Nils, Merchant Navy | 1922 | | Leiesten |
| | Overmeire, Franciscus van, Merchant Navy | 1897 | -1942 | Mendanau + |
| | Overment, , British Army | | | Brinkburn |
| | Overmire, Kenneth, USN | | | Esso Baton Rouge |
| | Overocker, Arthur Herbert, USN | 1925 | -1998 | Hahira |
| | Overrett, P.W., Merchant Navy | | | Fort Bellingham |
| | Overstreet, William Elwood, USNR | | | USS Barr (DE 576) |
| | Overstreet, Jr., George Philmore, USN | | | USS Block Island (CVE 21) |
| | Overton, John Joseph, RN | 1919 | -1939 | HMS Royal Oak (08) + |
| | Overton, Henry Victor, RN | | -1942 | HMS Grove (L 77) + |
| | Overton, Dent Alfred, RN | | -1943 | HMS Itchen (K 227) + |
| | Overton, Ray, USNR | | | USS LST-333 |
| | Overton, A., British Army | | | Tibia |
| | Overvag, Alfred, Civilian | | | Dorchester |
| | Overweel, Jan Koenraad Marie, Merchant Navy | 1914 | | Maasdam |
| | Overzier, Henricus Adrianus Antonius, Merchant Navy | 1905 | | Leto |
| | Ovesen, Nils, Merchant Navy | | | Lise |
| | Ovidi, Antonio, Regio Esercito | 1912 | -1942 | Laconia + |
| | Ovington, Douglas, RN | 1923 | -1942 | HMS Firedrake (H 79) + |
| | Ovost, Bartholomeus Julianus Jacobus van, Merchant Navy | 1918 | | Breedijk |
| | Ow Yeong Ying, , Merchant Navy | 1918 | -1942 | Otina + |
| | Owbridge, Frederick, Merchant Navy | 1889 | -1942 | Goolistan + |
| | Owen, Bernard John, FAA | 1905 | -1939 | HMS Courageous (50) + |
| | Owen, William Carodoc, FAA | 1916 | -1942 | HMS Avenger (D 14) + |
| | Owen, William, RN | 1925 | -1944 | HMS Cassandra (R 62) + |
| | Owen, Richard Gwynedd, RN | | -1940 | HMS Exmouth (H 02) + |
| | Owen, Peter Robert, RN | | -1944 | HMS Mahratta (G 23) + |
| | Owen, Ralph, RN | | -1940 | HMS Willamette Valley (X 39) + |
| | Owen, Charles, RNPS | 1921 | -1942 | HMS Rosemonde + |
| | Owen, Arthur, RN | 1923 | -1943 | HMS Itchen (K 227) + |
| | Owen, John, RN | 1926 | -1944 | HMS Gould (K 476) + |
| | Owen, William, RN | | -1945 | HMS Bluebell (K 80) + |
| | Owen, Maelgwyn, RN | 1926 | -1945 | HMS Lapwing (U 62) + |
| | Owen, James Byrell, USNR | | -1944 | USS Block Island (CVE 21) + |
| | Owen, Benjamin T., USN | | -1941 | USS Reuben James (DD 245) + |
| | Owen, Hugh Humphrey, Merchant Navy | 1920 | -1940 | Fircrest + |
| | Owen, John Richard, Merchant Navy | 1922 | -1942 | Avila Star + |
| | Owen, James William, British Army | | -1943 | Cornish City + |
| | Owen, Arthur Albert, Merchant Navy | 1894 | -1941 | Embassage + |
| | Owen, Thomas, Merchant Navy | 1912 | -1942 | San Fabian + |
| | Owen, Harry, RN | 1920 | -1942 | Président Doumer + |
| | Owen, Martyn, Merchant Navy | 1900 | -1940 | Lady Glanely + |
| | Owen, Edward Robert, Merchant Navy | | | Nigerian |
| | Owen, Melvyn, Merchant Navy | 1924 | -1942 | Melmore Head + |
| | Owen, Robert Goronwy, Merchant Navy | 1897 | -1942 | Somme + |
| | Owen, John, Merchant Navy | 1923 | -1942 | British Resource + |
| | Owen, Albert Sydney, Merchant Navy | 1890 | -1942 | Slavol + |
| | Owen, Eric Lloyd, Merchant Navy | 1922 | -1943 | British Dominion + |
| | Owen, William John, RN | 1924 | -1943 | Cordelia + |
| | Owen, Emlyn, Merchant Navy | 1920 | -1943 | Inverilen + |
| | Owen, Hugh Evan Emrys, Merchant Navy | 1906 | -1945 | Normandy Coast + |
| | Owen, Ralph, Merchant Navy | | | Lady Nelson |
| | Owen, Huw Jeffrey, Merchant Navy | 1917 | -1941 | Henri Mory + |
| | Owen, Richard Thomas, Merchant Navy | 1900 | -1941 | Henri Mory + |
| | Owen, Eva Doreen, Civilian | 1903 | -1943 | Melbourne Star + |
| | Owen, Walter Armour, Merchant Navy | | | City of Johannesburg |
| | Owen, James Joseph, Merchant Navy | | | East Wales |
| | Owen, Alfred John, Merchant Marine | 1893 | -1942 | Scapa Flow + |
| | Owen, E., Civilian | 1896 | | City of Simla |
| | Owen, I., Merchant Navy | 1921 | | Laertes |
| | Owen, Eugene Foshee, USNR | | | USS Block Island (CVE 21) |
| | Owen, David H., Merchant Marine | | | Esso Baton Rouge |
| | Owen, Oscar, Merchant Marine | 1905 | | Esso Bolivar |
| | Owen, Robert Pyrs, Merchant Navy | 1922 | | Mendoza |
| | Owen, John Edward Crewe, Merchant Marine | 1898 | -1966 | Irénée Du Pont |
| | Owens, John Francis, Merchant Marine | | -1943 | Meriwether Lewis + |
| | Owens, William John, RN | 1906 | -1940 | HMS Thistle (N 24) + |
| | Owens, George Arthur, RN | 1918 | -1941 | HMS Dunedin (D 93) + |
| | Owens, Arthur Frederick, RN | 1913 | -1943 | HMS Holcombe (L 56) + |
| | Owens, Bernard William, RN | 1922 | -1942 | HMS Arbutus (K 86) + |
| | Owens, Francis William, RN | 1920 | -1944 | HMS Asphodel (K 56) + |
| | Owens, Robert James, RN | 1926 | -1944 | HMS Ganilly (T 367) + |
| | Owens, Arley Royce, USN | 1920 | -1942 | USS Jacob Jones (DD 130) + |
| | Owens, Carl Leroy, USNR | | -1944 | USS LST-348 + |
| | Owens, John Edward, Merchant Navy | 1924 | -1941 | Carsbreck + |
| | Owens, William Elgar, Merchant Navy | 1911 | -1941 | Arakaka + |
| | Owens, Leslie, RN | | -1942 | Pennington Court + |
| | Owens, Robert Alfred, Merchant Navy | 1921 | -1940 | British Premier + |
| | Owens, Solomon, Merchant Navy | 1886 | -1942 | Chulmleigh + |
| | Owens, Benjamin Thomas, Merchant Navy | 1916 | -1942 | Empire Wagtail + |
| | Owens, Thomas William, Merchant Navy | 1903 | -1942 | Empire Fusilier + |
| | Owens, Owen, Merchant Navy | | | Point Pleasant Park |
| | Owens, Robert, | | | Grado |
| | Owens, Cornelius Joseph, USNR | | | USS Barr (DE 576) |
| | Owens, John, Merchant Marine | 1900 | | Examelia, Zaandam |
| | Owens, Julius Walter, USNR | | | USS Blakeley (DD 150) |
| | Owens, Jr., Grover Cleveland, USNR | | | USS Fechteler (DE 157) |
| | Owens, Robert Ellison, USNR | | | USS Fechteler (DE 157) |
| | Owens, Edgar W., Merchant Marine | 1922 | | Seakay |
| | Owens, Bennie George, USN | | | USS Block Island (CVE 21) |
| | Owens, Harley McCoy, USN | | | USS Leary (DD 158) |
| | Owens, Peter H., RN | | | HMS Royal Oak (08) |
| | Owens, William, RM | | | HMS Royal Oak (08) |
| | Owens, Kelton Lavere, USCG | | | USS Menges (DE 320) |
| | Owens, Lorie, Merchant Marine | 1910 | | Warrior |
| | Owens, Oamarn T., Merchant Navy | 1915 | | Opawa |
| | Owens, John, Merchant Navy | 1920 | | Adda |
| | Owensmith, Alan S.L., RN | | | HMS Courageous (50) |
| | Owers, Stanley Ernest William, RN | 1913 | -1942 | HMS Avenger (D 14) + |
| | Owler, Reginald John Anderson, Merchant Navy | 1917 | -1940 | Baron Blythswood + |
| | Owney, Archie Manalcus, Merchant Marine | 1912 | -1994 | Mathew Luckenbach |
| | Owren, Thor Scønang, Merchant Navy | 1920 | -1942 | Kongsgaard + |
| | Oxborough, George William, RCN | 1921 | -1942 | HMCS Spikenard (K 198) + |
| | Oxborough, George William, RNPS | 1915 | -1943 | HMS Bredon (T 223) + |
| | Oxendale, William, Merchant Navy | 1884 | | Adda |
| | Oxenham, Charles James, RN | 1905 | -1943 | HMS Itchen (K 227) + |
| | Oxenham, Henry Thomas, Merchant Navy | 1900 | -1942 | Empire Mica + |
| | Oxley, George Richard, RN | 1911 | -1939 | HMS Royal Oak (08) + |
| | Oxley, Harry, RN | 1919 | -1939 | HMS Royal Oak (08) + |
| | Oxley, John Henry, RN | 1910 | -1943 | HMS P-615 + |
| | Oxley, James Clifford, RN | 1923 | -1943 | HMS Puckeridge (L 108) + |
| | Oxley, Roy Wilson, Merchant Navy | 1924 | -1940 | Dalblair + |
| | Oxley, Ernest, FAA | 1914 | -1941 | Aguila + |
| | Oxley, Owen Alfred Guthrie, RN | | | HMS Courageous (50) |
| | Oxley, John, Merchant Navy | 1920 | | Athelviscount |
| | Oxspring, David, NAP | 1900 | -1941 | HMS Manistee (F 104) + |
| | Oxton, James Frederick, Merchant Navy | 1927 | | Fort Concord |
| | Oxås, Hans, Merchant Navy | | | Novasli |
| | Oyarzo Cárdenas, Zoilo, Merchant Navy | 1893 | -1942 | Tolten + |
| | Oyebo, Thompson, Merchant Navy | 1904 | | Sithonia |
| | Ozard, D., Merchant Navy | | | Boston |
| | Ozieulla, , Merchant Navy | 1906 | | Mariso |
| | Ozols, Zerzs, Merchant Navy | | | John P. Pedersen |
| | Ozon, Gerald Thomas, RCNVR | 1924 | -1944 | HMCS Valleyfield (K 329) + |
| | Ozoo Mian, , Merchant Navy | | -1943 | City of Pretoria + |
| | Ozzano, Luigi, Regio Esercito | 1922 | -1942 | Laconia + |
| | O’Berry, Sr., Alton Ray, Merchant Marine | 1906 | -1942 | Barbara, Ruth + |
| | O’Brien, James, Merchant Marine | | -1942 | Induna + |
| | O’Brien, William Joseph, Merchant Marine | | -1943 | Richard D. Spaight + |
| | O’Brien, James, Merchant Navy | 1900 | -1942 | Empire Hawksbill + |
| | O’Brien, Patrick, Merchant Navy | 1889 | -1942 | Arletta + |
| | O’Brien, Thomas, Merchant Navy | 1911 | -1940 | Oakcrest + |
| | O’Brien, Timothy Charles, Merchant Marine | 1899 | -1961 | Ceiba |
| | O’Brien, Francis D., Merchant Marine | | -1942 | J.A. Mowinckel |
| | O’Brien, John P., US Army | | | Dorchester |
| | O’Brien, Howard, USN | | | Esso Baton Rouge |
| | O’Brien, Clifford, Merchant Navy | 1903 | | La Carriere |
| | O’Brien, Patrick Albert, RN | 1922 | | Empire Kingsley |
| | O’Byrne, Pierce Leonard, Merchant Navy | 1919 | -2001 | Otterpool |
| | O’Connell, Jeremiah, Merchant Navy | 1909 | -1942 | Baron Newlands + |
| | O’Connell, Eldridge James, Merchant Marine | 1905 | -1977 | Esso Bolivar |
| | O’Connor, Jr., Charles Francis, USNR | 1923 | -2009 | Keystone |
| | O’Flanagan, Francis, RN | 1900 | -1971 | HMS LST-362 |
| | O’Handley, John, Merchant Navy | 1921 | -1942 | Gandia + |
| | O’Leary, Phillip John, RN | 1922 | -1942 | HMS Arbutus (K 86) + |
| | O’Leary, Daniel, Merchant Navy | 1915 | | Coimbra |
| | O’Neal, Charles Bertram, USN | | -1942 | USS Jacob Jones (DD 130) + |
| | O’Neal, William Thomas, Merchant Marine | 1908 | -1942 | Lake Osweya + |
| | O’Neal, James H., Merchant Marine | | | E.M. Clark |
| | O’Neill, Hugh, Merchant Navy | 1922 | -1942 | Stangarth + |
| | O’Neill, Lawrence, Merchant Navy | 1907 | | Luimneach |
| | O’Niel, James Leroy, USN | | -1942 | USS Jacob Jones (DD 130) + |
| | O’Niel, André, Merchant Navy | | -1942 | Nordvangen + |
| | O’Rear, Jack Mitchell, USN | 1925 | -1980 | Andrea F. Luckenbach |
| | O’Riordan, Daniel, Merchant Navy | 1908 | -1942 | Empire Steel + |
| | O’Rourke, John J., Merchant Marine | 1889 | | Venore |
| | O’Shea, John, Merchant Navy | 1916 | | San Demetrio |
| | O’Sullivan, Denis Patrick, Merchant Navy | 1916 | | Waynegate |
| | O’Toole, Martin, Merchant Navy | | -1942 | Spreewald + |
1591 people located. 969 of them died in the war.