German submarine U-100 (1940)

U-100 was a Type VIIB U-boat of Nazi Germany's Kriegsmarine during World War II. Her keel was laid down on 11 January 1939 by Friedrich Krupp Germaniawerft in Kiel as yard number 597 and she was commissioned on 7 December 1940 under the command of Kapitänleutnant Joachim Schepke.

U-100 conducted five war patrols, sinking eight ships for a total of 47,845 gross register tons (GRT) and damaging one ship of 3,672 GRT. She primarily operated in the North Atlantic against Allied convoys.

She gained notoriety under Schepke's command, who was known for his aggressive tactics. However, both U-100 and Schepke were lost on 17 March 1941 after a depth charge attack by the British destroyers HMS Walker and HMS Vanoc.

The circumstances of Schepke's death are debated. Initial British reports suggested he was captured after U-100 was sunk, but later investigation revealed he likely drowned. The attack also caused significant damage to U-100, which was scuttled shortly after being abandoned. The sinking of U-100 and the loss of Schepke was a significant blow to the German U-boat campaign in the Atlantic.

The wreck of U-100 lies in the North Atlantic, approximately 400 nautical miles west of Ireland.