113th MI Group Chicago Field Office

The 113th Military Intelligence (MI) Group, with its Chicago Field Office, was an integral element of the U.S. Army’s domestic counterintelligence and security operations during the Cold War era. Activated in the late 1950s, the Group was tasked with conducting investigations, surveillance, and liaison activities to detect and neutralize espionage, subversion, and other threats within its area of responsibility, which included the Chicago metropolitan region. The field office worked closely with local law enforcement and federal agencies, particularly during periods of heightened domestic unrest in the 1960s and 1970s. The 113th MI Group, along with its field offices, was ultimately inactivated in 1977 as part of a broader reorganization and reduction of Army intelligence activities within the United States.