The Iron Cross was established in 1813 in Breslau and given to soldiers in the wars against Napoleon. The Iron Cross was reauthorized in 1914 by Emperor Wilhelm II when the First World War started (see the WWI U-boat decoration).

The Iron Cross, the most famous German war decoration, was awarded in several classes:

The Großkreuz was only awarded once, to Hermann Göring in July 1940.

Das Eiserne Kreuz 1. Klasse

The Iron Cross 1st Class was worn on the left side of jacket.

The first EK 1 awarded to the U-Boat-force by order of the CinC Kriegsmarine went to the commander of U-29 on 18 September 1939 (delivered when the boat arrived in port on 26 Sep). Successful commanders often received both Iron Crosses after their first patrol, like Kptlt. Kentrat (U-74) and Kptlt. Mützelburg (U-203).

Kptlt. Fritz-Julius Lemp showing 3 grades of the Iron Cross; 2nd class ribbon on the button hole, 1st class Iron Cross on his left side and finally the Knights Cross around his neck.

Three officers from U-453 wearing the Iron Cross 1st Class, in the middle with the Knights Cross the commander Kptlt. Freiherr von Schlippenbach

Kptlt. Otto Kretschmer with EK I

Bar to the Iron Cross (Spange zum Eisernen Kreuz)

The Bar to the Iron Cross was used to indicate the award of the 1st or 2nd class Iron Cross to someone who won the same decoration in the First World War. The bar was worn clipped to the uniform jacket above the 1st class 1914 medal, or in the case of the 2nd class, on the ribbon.