BrightCyber Blog

Women’s History Month: Women of Cryptography

In honor of Women’s History Month, we are bringing recognition to four women who impacted history with their contributions to cryptography and code decryption prior to 1950. These women have broken codes, uncovered Nazi spy rings, and caught smugglers in the Prohibition era. Though they were hardly recognized during their time, with one even having credit stolen by Edgar J. Hoover, they have received medals and awards post humorously. In no particular order, our ladies of history are Agnes Driscoll, Elizabeth Friedman, Genevieve Grotjan, and Joan Clarke.

Agnes Meyer “Madame X” Driscoll

Agnes Driscoll

Born 1889- Died 1971

Agnes Meyer Driscoll was born 1889 in Illinois. She enlisted in the United States Navy in 1918 when women were starting to be able to enlist during World War I. Through hard work, she became the Leading Crypto Analyst for the United States Navy until her retirement in 1949. Her career spanned thirty years. During that career, she helped co-develop one of the U.S. Navy cipher machines. Also, she helped break the Japanese Navy manual code, known as the Red Book Code in the 1926. Following the Red Book Code, she helped crack the Blue book code in the 1930. She also led an attack on the Japanese M-1 cipher machine, which was used to encrypt the messages of Japanese naval attaches around the world.

Elizabeth Friedman

Elizabeth Friedman

Born 1892- Died 1980

Elizabeth Friedman, born Elizabeth Smith in 1892, grew up in Indiana. She married William Friedman in 1917. She was the first woman to run a cryptanalytic unit under the U.S. Coast Guard to monitor illicit smuggling rings. She was responsible for breaking codes used by narcotic and alcohol smugglers during the Prohibition Era. She solved over 12,000 rum-runner’s messages in three years. She also uncovered a Nazi Spy ring operating across South America in 1943. Though credit for the discovery initially went to Edgar J. Hoover, she later would receive the credit she earned.

Genevieve Grotjan-Feinstein

Genevieve Grotjan-Feinstein

Born 1913- Died 2006

Genevieve Grotjan-Feinstein was born April 30, 1913 in Buffalo, NY. She was hired by William Friedman, Elizabeth Friedman’s husband, for the Army Signal Intelligence Service (SIS) in 1939. In 1940, she made a discovery that lead to the breaking of the “Purple” Code. Breaking this code led to the U.S. creating their own machine which was able to intercept almost all messages exchanged between the Japanese Government and its embassies in foreign countries. Because of her accomplishment, she was assigned to the Soviet problem in October 1943. The project she worked on was known as “Verona”. “Verona” was trying to decode encrypted messages sent by the Soviet KGB and Main Intelligence Directorate. She excelled in the project and had a breakthrough in the code which would go on to be known as “.. the most important single cryptanalytic break in the whole history of Verona.”

Joan Clarke

Joan Clarke

Born 1917- Died 1996

Joan Clarke can be seen portrayed by Keira Knightly in the movie Enigma Code alongside Benedict Cumberbach. Together, they decrypted Enigma messages. Clarke was born in 1917 in West Norwood, London, England. In 1940, she was recruited to the Government Code and Cypher School. She famously worked in Bletchley Park’s Hut 8. She was the only female practitioner of Banburismus- a process of cryptanalytics developed by Turing which reduced the need for electromechanical devices used to decipher German encrypted messages in WWII. She worked closely with Turing and, together, they cracked the Enigma Code. Clarke and Turing’s work has thought to have shortened WWII by as much as two years.


Women have made significant discoveries that have altered the course of history. These women have proven that anyone can excell in the field. Driscoll, Friedman, Feinstein, and Clarke‘s contributions are now being recognized for the ground-breaking work that it was.

Happy Women’s History Month!


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Findling, Megan (2013). “Feinstein, Genevieve Grotjan (1912–2006)”. In Tendrich Frank, Lisa (ed.). Encyclopedia of American Women at War: From the Home Front to the Battlefields. ABC-CLIO. pp. 215–217. ISBN 978-1-59884-443-6.

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