At its peak in January 1945, 10,000 people worked at Bletchley Park, reading 4000 messages a day, decrypting German and Japanese communications and helping the Allies to victory. But while we know that Bletchley was the centre of Britain's World War II code-breaking, how did its efforts actually change the course of the war?

Enigma: How Breaking the Code Helped Win World War II tells the story of Bletchley's role in defeating U-boats in the Atlantic, breaking the Japanese codes, helping the Allies to victory in North Africa, deciphering the German military intelligence code, learning of most German positions in western Europe before the Normandy Landings, defeating the Italian Navy in the Mediterranean, and helping sink the German battleship Scharnhorst off Norway.

In tracing these events, the book also delves into the stories of major Bletchley characters, 'boffins' such as Alan Turing and Gordon Welchman, and 'Debs' such as Joan Clarke and Margaret Rock. An accessible work of military history that ranges across air, land and naval warfare, the book also touches on the story of early computer science.

Illustrated with 120 black-&-white and colour photographs, artworks and maps, Enigma: How Breaking the Code Helped Win World War II is an authoritative and novel perspective on WWII history.