From early 1942, the German battleship "Tirpitz" posed a significant threat to the Allied convoys transporting supplies through the Norwegian Sea to the Soviet Union. Stationed in fjords on the Norwegian coast, the ship was capable of overwhelming the close-escort forces assigned to the Arctic convoys. "Tirpitz" could also potentially attempt to enter the North Atlantic to attack Allied convoys travelling to the United Kingdom, as her sister ship "Bismarck" had sought to do in May 1941. To counter these threats, the Allies needed to keep a powerful force of warships with the British Home Fleet, and capital ships accompanied most convoys part of the way to the Soviet Union.