7 Dec, 1941
USS Thresher (Lt.Cdr. W.L. Anderson) was nearing Pearl Harbour, after conducting a simulated war patrol north of Midway, when the Japanese attacked. She returned to Pearl Harbour the next day.

30 Dec, 1941
USS Thresher (Lt.Cdr. W.L. Anderson) departs Pearl Harbour for her 2nd war patrol. She was ordered to patrol in the Marshall and Mariana Islands area.

26 Feb, 1942
USS Thresher (Lt.Cdr. W.L. Anderson) ended her 2nd war patrol at Pearl Harbour.

23 Mar, 1942
USS Thresher (Lt.Cdr. W.L. Anderson) left Pearl Harbour for her 3th war patrol. She was ordered to patrol in Japanese home waters.

10 Apr, 1942
USS Thresher (Lt.Cdr. W.L. Anderson) torpedoes and sinks the Japanese transport ship Sado Maru (3039 GRT) about 5 nautical miles north of Oshima, near the entrance to Tokyo Bay, Honshu, Japan in position 34º59'N, 139º29'E. (see map)

29 Apr, 1942
USS Thresher (Lt.Cdr. W.L. Anderson) ended her 3th war patrol at Pearl Harbour.

26 Jun, 1942
USS Thresher (Lt.Cdr. W.J. Millican) departs Pearl Harbour for her 4th war patrol. She is ordered to patrol in the Marshall / Caroline Islands area.

9 Jul, 1942
USS Thresher (Lt.Cdr. W.J. Millican) torpedoes and sinks the Japanese torpedo recovery vessel Shinsho Maru (4836 GRT) at the entrance to Kwajalein Atoll, Marshall Islands in position 08º43'N, 167º33'E. (see map)

15 Aug, 1942
USS Thresher (Lt.Cdr. W.J. Millican) ended her 4th war patrol at Fremantle, Australia.

15 Sep, 1942
USS Thresher (Lt.Cdr. W.J. Millican) departs Fremantle for her 5th war patrol. She is ordered to patrol in the gulf of Siam and lay mines there.

16 Oct, 1942
USS Thresher (Lt.Cdr. W.J. Millican) lays mines in the Gulf of Siam in the approaches to Bangkok.

12 Nov, 1942
USS Thresher (Lt.Cdr. W.J. Millican) ends her 5th war patrol at Fremantle.

16 Dec, 1942
USS Thresher (Lt.Cdr. W.J. Millican) departs Fremantle for her 6th war patrol. She is ordered to patrol in the South China Sea.

30 Dec, 1942
USS Thresher (Lt.Cdr. W.J. Millican) damages the Japanese merchant Hachian Maru (2733 GRT) with gunfire about 120 nautical miles west of Mata Siri Island, off the southeastern tip of Borneo. The Japanese ship is finished off with one torpedo and sinks in position 04º45'N, 113º54'E. (see map)

10 Jan, 1943
USS Thresher (Lt.Cdr. W.J. Millican) ends her 6th war patrol at Fremantle.

25 Jan, 1943
USS Thresher (Lt.Cdr. W.J. Millican) departs Fremantle for her 7th war patrol. She is ordered to patrol in the Netherlands East Indies.

14 Feb, 1943
USS Thresher (Lt.Cdr. W.J. Millican) attacks the Japanese submarine I-162 (offsite link) off the Lesser Sundas in position 06º05'S, 105º47'E. Thresher fires two torpedoes, unfirtunately one is a dud and the other misses. (see map)

21 Feb, 1943
USS Thresher (Lt.Cdr. W.J. Millican) torpedoes and damages the Japanese transport ship Kuwayama Maru (5724 GRT) off Soembawa Island, Netherlands East Indies in position 07º53'S, 119º13'E. The damaged Japanese ship sinks the following day. (see map)

2 Mar, 1943
USS Thresher (Lt.Cdr. W.J. Millican) torpedoes and sinks the Japanese tanker Toen Maru (5332 GRT) in the southern Makassar Strait, Netherlands East Indies in position 03º29'S, 117º17'E. (see map)

10 Mar, 1943
USS Thresher (Lt.Cdr. W.J. Millican) ends her 7th war patrol at Fremantle.

4 Apr, 1943
USS Thresher (Lt.Cdr. H. Hull) departs Fremantle for her 8th war patrol.

23 May, 1943
USS Thresher (Lt.Cdr. H. Hull) ends her 8th war patrol at Fremantle.

1 Jul, 1943
While on her 9th war patrol USS Thresher (Lt.Cdr. H. Hull) attacked a Japanese convoy off the northwest coast of Celebes, in the Straits of Makassar. She torpedoed and damaged the Japanese destroyer Hokaze (offsite link) in position 00º43'N, 119º34'E and torpedoes and sinks the Japanese transport ship Yoneyama Maru (5274 GRT) in position 00º20'N, 119º32'E about 40 nautical from Balikpapan. Hokaze is grounded in Sibaya harbor, Celebes, to prevent her from sinking and to permit her to be salvaged. (see map)

9 Jul, 1943
USS Thresher (Lt.Cdr. H. Hull) lands men, 500 pounds of stores and 40,000 rounds of ammunition on the west coast of Negros near Catmon Point. Thresher now left the Philippines and proceeded to Pearl Harbour where she was to end her 9th patrol. After arriving at Pearl Harbour Thresher was ordered to the Mare Island Navy Yard for an overhaul.

1 Nov, 1943
With her overhaul completed USS Thresher (Lt.Cdr. H. Hull) departs Pearl Harbour for her 10th war patrol. She is ordered to patrol in the Caroline Islands area.

12 Nov, 1943
USS Thresher (Lt.Cdr. H. Hull) torpedoes and sinks the Japanese transport ship Muko Maru (4862 GRT) north of Truk in position 09º02'N, 152º46'E. Unfortunately Thresher is damaged by depth charges dropped by the escorts and is forced to terminate her patrol. (see map)

29 Nov, 1943
USS Thresher (Lt.Cdr. H. Hull) ends her 10th war patrol at Pearl Harbour.

27 Dec, 1943
USS Thresher (Lt.Cdr. D.C. MacMillan) left Pearl Harbour for her 11th war patrol. She was ordered to patrol in the South China Sea.

10 Jan, 1944
USS Thresher (Lt.Cdr. D.C. MacMillan) sinks the Japanese sailing vessel Horai Maru (91 GRT) with gunfire in the South China Sea.

15 Jan, 1944
USS Thresher (Lt.Cdr. D.C. MacMillan) torpedoes and sinks the Japanese transport ship Toho Maru (4092 GRT) and the Japanese tanker Tatsuno Maru (6960 GRT) about 75 nautical miles north of Luzon, Philippines in position 20º00'N, 120º51'E. (see map)

27 Jan, 1944
USS Thresher (Lt.Cdr. D.C. MacMillan) torpedoes and sinks the Japanese transport ship Kosei Maru (2205 GRT) and the Japanese merchant Kikuzuki Maru (1266 GRT) about 70 nautical miles south-west of Formosa in position 22º11'N, 119º12'E. (see map)

18 Feb, 1944
USS Thresher (Lt.Cdr. D.C. MacMillan) ends her 11th war patrol at Pearl Harbour.

18 Mar, 1944
USS Thresher (Lt.Cdr. D.C. MacMillan) left Pearl Harbour for her 12th war patrol. She was ordered to patrol in the Caroline Islands area.

8 May, 1944
USS Thresher (Lt.Cdr. D.C. MacMillan) ends her 12th war patrol at Pearl Harbour.

14 Jun, 1944
USS Thresher (Lt.Cdr. D.C. MacMillan) left Pearl Harbour for her 13th war patrol. She was ordered to patrol in the South China Sea.

16 Jul, 1944
USS Thresher (Lt.Cdr. D.C. MacMillan) torpedoes and sinks the Japanese transport ship Shozen Maru (2838 GRT) off northern Luzon, Philippines in position 18º23'N, 119º06'E, and torpedoes and damages the Japanese merchant Sainei Maru (4916 GRT) in position 18º23'N, 119º32'E. This last ship sinks the following day. (see map)

27 Jul, 1944
USS Thresher (Lt.Cdr. D.C. MacMillan) ends her 13th war patrol at Midway.

23 Aug, 1944
USS Thresher (Lt.Cdr. J.R. Middleton, Jr) departs Midway for her 14th war patrol. She was ordered to patrol in the Yellow and East China Seas.

18 Sep, 1944
USS Thresher (Lt.Cdr. J.R. Middleton, Jr) torpedoes and sinks the Japanese transport ship Gyoku Maru (6854 GRT) in the Yellow Sea in position 35º02'N, 124º24'E. (see map)

25 Sep, 1944
USS Thresher (Lt.Cdr. J.R. Middleton, Jr) torpedoes and sinks the Japanese merchant Nissei Maru (1468 GRT) in the Yellow Sea in position 37º32'N, 124º33'E. (see map)

26 Sep, 1944
USS Thresher (Lt.Cdr. J.R. Middleton, Jr) torpedoes and sinks the Japanese merchant Koetsu Maru (873 GRT) in the Yellow Sea in position 37º13'N, 123º48'E. (see map)

3 Oct, 1944
USS Thresher (Lt.Cdr. J.R. Middleton, Jr) sinks the Japanese guardboat Nanshin Maru No.28 (83 GRT) with gunfire north-northwest of Marcus Island in position 30º49'N, 153º26'E. (see map)

12 Oct, 1944
USS Thresher (Lt.Cdr. J.R. Middleton, Jr) ends her 14th war patrol at Pearl Harbour.

31 Jan, 1945
USS Thresher (Lt.Cdr. J.R. Middleton, Jr) departs Pearl Harbour for her 15th and last war patrol. She was ordered to patrol north of Luzon.

24 Apr, 1945
USS Thresher (Lt.Cdr. J.R. Middleton, Jr) ends her 15th and last war patrol at Pearl Harbour. She was now assigned to training duties.