A total of 74 British decorations, including 5 VC's, plus 4 French Croix de Guerres resulted from the St. Nazaire action. The raid cost Britain 169 killed and some 200 prisoners.
The aim of the Tirpitz, like its sister ship the Bismarck, was commerce raider. The Bismarck in a single action engaged the new battleship Prince of Wales, and the battlecruiser Hood. The Hood was destroyed with a loss of over 1,400 lives. The Bismarck, also damaged, initially headed for St. Nazaire, the only port under German control where repairs were possible. Hence the fear of Tirpitz and the desire to deny the ship's only refuge.
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Raid on St. Nazaire: Operation Chariot During World War II » HistoryNet - From the World's Largest History Magazine Publisher