German U-boat bases in occupied Norway

German U-boat bases in occupied Norway operated between 1940 and 1945, when the Kriegsmarine (German navy), converted several naval bases in Norway into submarine bases. Norwegian coastal cities became available to the Kriegsmarine after the invasion of Denmark and Norway in April 1940. Following the conclusion of the Norwegian Campaign (June 1940), the occupying Germans began to transfer U-boats stationed in Germany to many Norwegian port cities such as Bergen, Narvik, Trondheim, Hammerfest and Kirkenes. Initial planning for many U-boat bunkers began in late 1940. Starting in 1941, the Todt Organisation began the construction of bunkers in Bergen and Trondheim. These bunkers were completed by Weyss & Freytagg AG between 1942 and 1943.

The Kriegsmarine generally used U-boats stationed in Norway to extend its range of operation in the North Atlantic and Arctic Oceans. The Norwegian bases housed U-boats that took part in the interception of Allied convoys crossing the Arctic Ocean to the Soviet Union. Following the liberation of France by the Western Allies in 1944, U-boat activity in many Norwegian ports increased. With the French ports captured or cut off, many German U-boats re-located to Norwegian port cities.

During the German occupation of Norway, the Kriegsmarine stationed over 240 U-boats in the Nordic country at one time or another, most of them members of the 11th U-boat Flotilla, which had 190 U-boats in its fleet during the flotilla's entire career. Other well-known flotillas in Norway included the 13th and 14th Flotillas.

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