Sixth Corps Area was a Corps area, effectively a military district, of the United States Army from 1921 to the 1940s.[1] The headquarters was established at Fort Sheridan, Illinois, in August 1920, from portions of the former Central Department, but then moved to the U.S. Post Office Building at 1819 West Pershing Road in Chicago on 10 October 1921.[1]
The corps area covered the states of Wisconsin, Michigan and Illinois and Jefferson Barracks, Missouri.[1] It was responsible for the mobilization, administration, and training of units of the Second and Fifth Armies, I Cavalry Corps (Regular Army, but inactive, 1927-1940), VI Army Corps (6th Division, 32d and 33rd Divisions) and XVI Army Corps (85th, 86th, 101st Divisions), select GHQ Reserve units, the Zone of the Interior support units of the Sixth Corps Area Support Command, and 21st Airship Group at Scott Field, Illinois (12 August 1936-19 February 1939).[2] 2d Balloon Squadron was assigned to Sixth Corps Area from 20 May 1930 - 30 December 1940.[3]
On 24 March 1923, the 21st Aero Squadron was reconstituted as the 21st Observation Squadron of the United States Army Air Service. The Army activated the unit as a "Regular Army Inactive" squadron,[4] meaning that although it was a Regular Army unit, it was manned with reserve personnel.[5] It was assigned to the 9th Observation Group in the Sixth Corps Area. The 21st's designated Active Associate unit was the 15th Observation Squadron, at Chanute Field, Illinois, which was also its designated mobilization station. In 1927 it was withdrawn from the Sixth Corps Area and reassigned to the Fourth Corps Area.[4]
Paul Malone was promoted to major general and assumed command of the Sixth Corps Area in Chicago in 1928. Malone then left the United States in April 1929 and embarked for a new assignment in the Philippines.[6]
Major active duty installations in the corps area included Fort Brady, Chanute Field, Camp Custer, Jefferson Barracks, Scott Field, Fort Sheridan, and Fort Wayne.[7] Camp Douglas and Camp Grant were among the National Guard installations.[7]
Lieutenant General (AUS) Walton Walker was assigned as the commander of the succeeding Sixth Service Command and the Fifth Army, headquartered in Chicago, from May 1946 to September 1948. He was then sent to Japan.