U-Boat

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U-boat is the anglicized version of the German word U-Boot, itself an abbreviation of Unterseeboot (undersea boat), and refers to military submarines operated by Germany, particularly in World War I and World War II. Although in theory U-boats could have been useful fleet weapons against enemy naval warships, in practice they were most effectively used in an economic warfare role (commerce raiding), 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 the British Empire and the United States to the islands of Great Britain.

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