Originally it was a girls' school and later the headquarters of the United States Army's Signal Intelligence Service (SIS) cryptography operations during World War II.
Gardner and his colleagues began analytically reconstructing the KGB (the Soviet Union's Committee for State Security) spy agency codebooks.
SIS's reporting procedures did not seem appropriate because the decrypted messages could not even be paraphrased for Arlington Hall's regular intelligence customers without divulging their source.
In late August or early September 1947, the Federal Bureau of Investigation (FBI) was informed that the Army Security Agency had begun to break into Soviet espionage messages.
Beginning in January 1963, Arlington Hall served as the premier facility of the newly created Defense Intelligence Agency (DIA).
Arlington Hall was also home in the late 1950s and early 1960s to the Armed Services Technical Information Agency (ASTIA) which disseminated classified research to defense contractors.
[8]In January 2008, construction workers discovered an unexploded Civil War-era Parrott rifle shell underneath Arlington Hall.
The western portion of Arlington Hall site presently houses the Army National Guard Readiness Center, which was named for Herbert R. Temple Jr. in 2017.