The German submarine U-47, under the command of Kapitänleutnant Günther Prien, is famous for its audacious raid on the British fleet anchorage at Scapa Flow on October 14, 1939. U-47 penetrated the defenses of the heavily fortified anchorage, fired torpedoes, and sank the Royal Navy battleship HMS Royal Oak, killing 833 sailors. The successful raid was a major propaganda victory for Nazi Germany.
