Frank B. Rowlett passed away on June 29, 1998 at the age of 90. Mr. Rowlett was the last of William Friedman's original employees, hired for the Army's Signal Intelligence Service in 1930.
Frank Rowlett was born on May 2, 1908 in Rose Hill, Virginia. He received a B.A. from Emory and Henry College with a major in Mathematics and Chemistry. He was hired by William Friedman as a "junior cryptanalyst" for the SIS on April Fool's Day in 1930; shortly thereafter he was followed in the SIS by Abraham Sinkov and Solomon Kullback.
During the 1930s, Rowlett and his colleagues, after a lengthy period of training, worked as both cryptologists and cryptanalysts. They compiled codes and ciphers for use by the U.S. Army and began solving a number of foreign systems, notably Japanese. In the mid-1930s, Rowlett and his colleagues solved the first Japanese machine system for encipherment of diplomatic communications, known to the Americans as RED. From 1939-40, Rowlett played a major role in solving a much more sophisticated Japanese diplomatic cipher machine, nicknamed PURPLE by the U.S. When asked what his greatest contribution to this effort was, Rowlett once said, "I was the one who believed it could be done."
Friedman and Rowlett also had crucial roles in protecting American communications during World War II. Working with the U.S. Navy, they helped design the SIGABA, the cipher machine which was never solved by the Axis during the war. The security of this machine was also an important factor in saving American lives in combat. (In 1964, Congress awarded Rowlett $100,000 as partial compensation for his classified cryptologic inventions).
In addition to having highly-developed cryptanalytic skills, Rowlett was a good manager, and he rose quickly within the organization. From 1943-45 he was Chief of the General Cryptanalytic Branch and from 1945-47 he was chief of the Intelligence Division. From 1949-52, he was technical director in the Office of Operations of the Armed Forces Security Agency, the predecessor to NSA.
Rowlett differed with General Ralph Canine, the first director of NSA, over personnel movements, including his own. Acting on his differences, he transferred to the Central Intelligence Agency in 1952, and worked there until 1958. At that time he returned to NSA as a Special Assistant to the Director. In 1965, Rowlett became commandant of the National Cryptologic School. He retired from federal service in 1966.
Because of his importance in the protection of American communications, the Information Assurance organization has named its highest award the Frank Byron Rowlett Award.
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