Parker Hitt

Colonel Parker Hitt (August 27, 1878 – March 2, 1971) was a United States Army officer and a pioneer in the field of cryptology. Often cited as the "father of modern American military cryptology," Hitt authored the first practical work on military ciphers in the United States in over a century and invented foundational cryptographic devices that remained in use through World War II.

Early life and education Parker Hitt was born in Indianapolis, Indiana, on August 27, 1878. He served as a sergeant in the 2nd U.S. Volunteer Engineers in Cuba before being commissioned as a second lieutenant in the 22nd Infantry in 1899. Following the U.S. entry into World War I, General John J. Pershing selected Hitt for his staff in the American Expeditionary Forces (AEF).

Hitt retired as a colonel in 1928 but was recalled to active duty in 1940 at the age of 62.

Manual for the Solution of Military Ciphers In 1916, Hitt published his seminal work, Manual for the Solution of Military Ciphers. It was the first practical U.S. instructional text on cryptanalysis in a century.

Inventions Finding the official Army field cipher insecure, Hitt proposed mechanical alternatives: The Cylinder Cipher: In 1912, Hitt built a prototype cylindrical device. This design was later refined by Major Joseph Mauborgne into the M-94, which the Army adopted in 1922 and used for over two decades. The Sliding Strip Cipher: Hitt developed a flat version of the cylinder device using alphabetic strips. This evolved into the M-138-A, used extensively by the State Department and U.S. Navy during the 1930s and World War II. Their daughter, Mary Lueise Hitt, also served as a "code girl" and teleprinter operator during World War II. Hitt Hall at Fort Huachuca was named in his honor in 1995. During the 1930s, he was a key mentor to the American Cryptogram Association (ACA), providing technical advice to authors like Helen Fouché Gaines.