The Signal Intelligence Service (SIS) was the United States Army codebreaking division through World War II. It was founded in 1930 to compile codes for the Army. It was renamed the Signal Security Agency in 1943, and in September 1945, became the Army Security Agency.[1] For most of the war it was headquartered at Arlington Hall (former campus of Arlington Hall Junior College for Women), on Arlington Boulevard in Arlington, Virginia, across the Potomac River from Washington (D.C.). During World War II, it became known as the Army Security Agency, and its resources were reassigned to the newly established National Security Agency (NSA).