Title: U-boat warfare
Subjects: Campaigns, Germany, Germany Naval operations, Germany. Kriegsmarine, History, Naval operations, Submarine, Submarine warfare, Submarines (Ships), World War, 1939-1945, German Naval operations, Naval tactics, World war, 1939-1945, campaigns, World war, 1939-1945, naval operations, submarine
Places: Atlantic Ocean, Germany
Time periods: 20th century, World War, 1939-1945