Cryptologic Bytes

"On This Date in History" Calendar

1998: Frank Rowlett, cryptologic pioneer, died.

Saturday, June 29, 2024

29 June 1998: Cryptologic pioneer Frank Rowlett, one of William Friedman's first hires for Signal Intelligence Service, died on this date.

He was inducted into the NSA Cryptologic Hall of Honor in 1999 (see link below). Because of his importance in the protection of American communications, the Information Assurance organization has named its highest award the Frank Byron Rowlett Award.

From the Emory & Henry College Web site:

Born at Rose Hill in Lee County, Virginia, Frank Rowlett graduated from Emory & Henry College in June 1929 with majors in mathematics and chemistry and the Byars Medal in Science. In April 1930, he became the first junior cryptanalyst in the U.S. Army Signal Intelligence Service in the War Department in Washington, D.C. Eventually, he led a War Department group in writing ciphers for the U.S. Army, and breaking foreign code systems–notably Japanese codes.

Rowlett’s group solved the first Japanese system for encrypting diplomatic communications, which they called Red. In 1940, in a step ultimately critical to American and Allied victory in World War II, Rowlett’s group solved the more complex and sophisticated Japanese code they named Purple. Unaware their code had been broken the Japanese used Purple throughout the War, enabling American and Allied leaders to know important Japanese and German secrets by reading all messages passed between Tokyo and Berlin.

Working with the U.S. Navy, Rowlett designed communications codes that German, Japanese, and Italian code breakers never solved. Rowlett’s work saved the lives of thousands of American and Allied soldiers. Honored by President Johnson and by the U.S. Congress, Rowlett retired from federal service in 1966 as a founding father of the National Security Agency, which created a distinguished achievement award in his honor and named the Agency's academic center for training cryptanalysts Frank B. Rowlett Hall.


Check out the Cryptologic Bytes Archives for a wide variety of articles on all topics related to cryptology, codes and ciphers, related publications, Museums, and more.