U-boat

The Armistice terms of 1918 required Germany to surrender all its U-boats, and the Treaty of Versailles forbade it to possess them in the future. In 1935, however, Adolf Hitler's Germany repudiated the treaty and forcefully negotiated the right to build U-boats. Britain was ill-prepared in 1939 for a resumption of unrestricted submarine warfare, and during the early months of World