Women Cryptologists of World War II Stamps

Postal Service honors all of the women cryptologists of World War II, whose service played an inestimable role in the Allied victory.

The stamp art features an image from a World War II–era WAVES (Women Accepted for Volunteer Service) recruitment poster with an overlay of characters from the “Purple” code. The poster was designed by John Falter (1910–1982), who designed more than 300 recruiting posters during his military service. The Purple code was used by the Japanese government to encrypt diplomatic messages. Genevieve Grotjan, a cryptologist with the U.S. Army’s Signal Intelligence Service, discovered the key to cracking the code in September 1940. Her breakthrough allowed the United States to read and exploit the information conveyed in Japanese diplomatic messages for the duration of the war.