William Frederick Friedman
American cryptologist (1891-1969) · United States · On the map · Academics · Died at 78
William Frederick Friedman was a US Army cryptographer who ran the research division of the Army's Signal Intelligence Service (SIS) in the 1930s, and parts of its follow-on services into the 1950s.
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Photos 8
William and Elizebeth Friedman, recently married, at Riverbank in 1917
Riverbank Laboratories
W. F. Friedman in 1924
Friedman with an AT&T cipher machine
SIGABA cipher machine
Bust of Friedman on display at the National Cryptologic Museum, where he is identified as the "Dean of American Cryptology".
Declassified copy of confiscated 1965 "Friedman Lectures on Cryptology"Awards
About this person
In 1940, subordinates of his led by Frank Rowlett broke Japan's PURPLE cipher, thus disclosing Japanese diplomatic secrets before America's entrance into World War II.
