Enigma

The Enigma machine was a Polish invention adopted by Nazi Germany, and given to Japan, to ‘hide’ messages from the Allies. During WWII a great effort was made by England and the United States to decypher these messages. The English effort was named ‘Enigma’ and the United States effort was named ‘Ultra”. Allan Turing was instrumental in the English effort and Michael Friedman in the United States effort. Both were successful.

The books below describe the history of the machine and the efforts made to decipher it.