Government Code and Cypher School: Signals Intelligence Passed to the Prime Minister, Messages and Correspondence

A file of signals intelligence reports, messages, and correspondence issued by the Government Code and Cypher School and sent by the head ('C') of the Secret Intelligence Service (MI6) to the Prime Minister, Winston Churchill. This file includes the following reports on West Europe: a German Air Force (GAF) situation report, for November 25, stating that Allied advances open two gaps in the front line; and an evaluation of the British-U.S. methods of attack and the lessons to be learned, on November 21.