German submarines

U-boat is an anglicised version of the German word U-Boot [ˈuːboːt] ( listen), a shortening of Unterseeboot, literally "undersea boat". While the German term refers to any submarine, the English one (in common with several other languages) refers specifically to military submarines operated by Germany, particularly in the First and Second World Wars. Although at times they were efficient fleet weapons against enemy naval warships, they were most effectively used in an economic warfare role (commerce raiding) and enforcing a naval blockade against enemy shipping. The primary targets of the U-boat campaigns in both wars were the merchant convoys bringing supplies from Canada and other parts of the British Empire, and the United States to the United Kingdom and (during the Second World War) to the Soviet Union and the Allied territories in the Mediterranean.

Austro-Hungarian navy submarines were also known as U-boats.

The first submarine built in Germany, the three-man Brandtaucher, sank to the bottom of Kiel harbor on 1 February 1851 during a test dive. The inventor and engineer Wilhelm Bauer had designed this vessel in 1850, and Schweffel & Howaldt constructed it in Kiel. Dredging operations in 1887 rediscovered Brandtaucher; it was later raised and put on historical display in Germany.

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