Venona papers

The Venona project was a counterintelligence program initiated by the United States Army's Signal Intelligence Service (later the National Security Agency) that ran for nearly four decades, spanning 1943 to 1980. The purpose of the Venona project was the decryption of messages transmitted by the intelligence agencies of the Soviet Union, e.g. the NKVD, the KGB (First Chief Directorate) and the GRU (military intelligence). During the 37-year duration of the Venona project, the Signal Intelligence Service obtained approximately 3,000 Soviet messages (only some of which were ever decrypted); the Signal-Intelligence yield included discovery of the Cambridge Five espionage ring in the UK and Soviet espionage of the Manhattan Project in the U.S. The Venona project remained secret for more than 15 years after it concluded, and some of the decoded Soviet messages were not declassified and published until 1995.

During the initial years of the Cold War, the Venona project was a source of information on Soviet intelligence-gathering directed at the Western military powers. Although unknown to the public, and even to Presidents Franklin D. Roosevelt and Harry S. Truman, these programs were of importance concerning crucial events of the early Cold War. These included the Julius and Ethel Rosenberg spying case and the defections of Donald Maclean and Guy Burgess to the Soviet Union.

Most decipherable messages were transmitted and intercepted between 1942 and 1945. Sometime in 1945, the existence of the Venona program was revealed to the Soviet Union by cryptologist-analyst Bill Weisband, an NKVD agent in the U.S. Army’s SIGINT. These messages were slowly and gradually decrypted beginning in 1946 and continuing (many times at a low-level of effort in the latter years) through 1980, when the Venona program was terminated, and the remaining amount of effort that was being spent on it was moved to more important projects.

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