U-boat

German submarine

U-boats are naval submarines operated by Germany, especially during World War I and World War II. The term is an anglicized form of the German word U-Boot [ˈuːboːt] , a shortening of Unterseeboot (lit. 'under-sea boat'). Austro-Hungarian Navy submarines were also known as U-boats. U-boats are especially known for their use in unrestricted submarine warfare in both world wars, attempting to disrupt merchant traffic towards the United Kingdom to force them out of the war.

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