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NSA Historical Figures

Lambros D. Callimahos

2003 Hall of Honor Inductee

Lambros D. Callimahos was born December 16, 1910 on the island of Gezirah in the Nile near Cairo, to Greek parents and came to the United States at age four. When college age, he studied law at Rutgers before graduating from Julliard in 1933 with a degree in music. After a few years of concert touring as a flutist, Mr. Callimahos, an avid amateur cryptologist, joined the U.S. Army in 1941 and entered the cryptologic service.

After basic training, Mr. Callimahos taught cryptanalysis and Italian at the language department at Fort Monmouth. He graduated from Officer's Training School in 1942 and was supposed to spend the next several months developing a new cryptologic course with William Friedman. However, a chain of changes led to his enrollment in a Japanese course and subsequent assignment to New Delhi as assistant signals intelligence officer for the China-Burma-India Theater. When the war was over, finally, he was assigned to the Army Security Agency as Friedman's assistant.

Through the 1950s, Mr. Callimahos collaborated with Friedman on a variety of projects and developed his own famous class CA-400. This was an expansion of Friedman's original intensive-study senior cryptanalytic course. He taught 32 sessions of CA-400, for a total of 270 students. Graduates of CA-400, the elite among cryptanalysts, became members of the Dundee Society, a society made up by Mr. Callimahos named after the empty Dundee marmalade jar on his desk because he couldn't disclose the real purpose of the group, and played a crucial role in shaping cryptologic development at NSA.

A prolific writer of cryptologic literature, Mr. Callimahos was the author of over 40 books, monographs, and articles. He helped establish NSA's Technical Journal in 1955 and served as technical advisor to the publication for the rest of his career. He wrote articles on codes and ciphers for numerous reference works, including Encyclopedia Britannica.

By the end of his career, Mr. Callimahos was respected by his colleagues and students as a true Renaissance man: teacher, writer, linguist, cryptologist, and flutist. He was awarded the NSA Exceptional Civilian Service Award on 24 August 1976. Illness forced him to retire in late 1976.

Lambros Callimahos passed away on October 28, 1977.