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Women in American Cryptology Creating the Legacy

Genevieve Grotjan Feinstein

Genevieve Feinstein

Genevieve Feinstein hoped to become a math teacher. However, after taking the tests to become a professional government mathematician, she was offered a job with the Signal Intelligence Service (SIS). In 1939, Mrs. Feinstein was a cryptanalyst involved in the decryption and reading of Japanese diplomatic messages. In September 1940, she made a discovery that changed the course of history. Her successful breakthrough enabled the SIS to build an analog machine to decrypt the Japanese diplomatic messages, known as "Purple," throughout WWII.

Mrs. Feinstein followed her success with work on other Japanese cipher systems and as a pioneer in the cryptanalytic research section working on a variety of machine cipher systems. Following the war, she was assigned to the Soviet problem working on the Venona Project.


Historical Document | Date Posted: Jan 15, 2009