Intelligence
Found in 1 Collection or Record:
Microfilm copies of "ULTRA" signals
Consisting of intelligence from intercepted enemy communications, forwarded from the Admiralty to Allied Commands, "Cairo Series", June 1942-September 1943.
Generally being decrypts from the Government Code and Cipher School at Bletchley Park, Buckinghamshire, using the Enigma machine. The Enigma signals were given a special security classification, "MSS" (Most Secret Source) or "ULTRA".