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Undid revision 890819424 by ArnoldReinhold (talk)Unfortunately Ann Zeilinger Caracristi Graduated from College in 1942. While SIS existed from 1930 to 1942. SIS only recruited her in 1942 and sent her to study. Maybe she worked for the Army Security Agency.
Undid revision 890865278 by ArnoldReinhold (talk)
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[[Category:Signals intelligence of World War II]]
[[Category:Signals intelligence of World War II]]
[[Category:United States Army Signals Intelligence Service| ]]
[[Category:United States Army Signals Intelligence Service| ]]
[[Category:American women in World War II]]

Revision as of 18:55, 4 April 2019

The Signal Intelligence Service (SIS) was the United States Army codebreaking division, founded in 1930 and operating to 1942. It was headquartered at Arlington Hall (former campus of Arlington Hall Junior College for Women), on Arlington Boulevard in Arlington, Virginia, across the Potomac River from Washington (D.C.). During World War II, it became known as the Army Security Agency, and its resources were reassigned to the newly established National Security Agency (NSA).

History

The Signal Intelligence Service was a part of the U.S. Army Signal Corps so secret that outside the office of the Chief Signal officer, it did not officially exist. SIS was an early predecessor to the modern NSA. It was appropriated by the National Security Council who reassigned the resources into the modern NSA.

William Friedman began the division with three "junior cryptanalysts" in April 1930. Their names were Frank Rowlett, Abraham Sinkov, and Solomon Kullback. Before this, all three had been mathematics teachers and none had a cryptanalysis background. Friedman was a geneticist who developed his expertise in cryptology at George Fabyan's Riverbank Laboratories Cipher Department during 1915 to 1917, prior to World War I.[1] Besides breaking foreign codes,[2] they were responsible for just about anything to do with the U.S. Department of War's code systems. The SIS initially worked on an extremely limited budget, lacking the equipment it needed so that the analysts could intercept messages to practice decrypting.

Midway through World War II, in 1943, the Army Signal Intelligence Service (later the Army Security Agency) began intercepting Soviet (Russian) intelligence traffic sent mainly from New York City; they assigned the code name "Venona" to the project. Although the United States had become allies with the Soviet Union in 1941, many officials were suspicious of the communist government and society. By 1945, some 200,000 messages had been transcribed, a measure of Soviet activity.

On 20 December 1946, after the war and at a time of increasing US tensions with the Soviet Union, Meredith Gardner made the first break into the Venona code. Decrypted messages revealed the existence of Soviet espionage at the Los Alamos National Laboratory work on the top-secret Manhattan Project, where the atomic bomb had been developed and research continued. The Venona project was so highly classified, however, that the government never introduced evidence from these messages into court proceedings in prosecution of alleged espionage agents.

William Friedman (head of the SIS) Frank Rowlett (junior cryptanalyst) Abraham Sinkov (junior cryptanalyst) Solomon Kullback (junior cryptanalyst)

Intercept network

U.S. Army Signals Intelligence Service personnel at Arlington Hall (c. 1943)

The Army intercept network during WWII had six fixed stations, which concentrated on Japanese military signals and Axis diplomatic traffic.[3]

See also

References

  1. ^ "Cryptologic Almanac - NSA/CSS". Nsa.gov. 15 January 2009. Retrieved 15 February 2014.
  2. ^ Bernard A. Weisberger "Eavesdropping on the Rising Sun," American Heritage, Fall 2009.
  3. ^ Budiansky 2000, p. 357.