The 191st Infantry Brigade was constituted on 24 June 1921 in the Organized Reserves as Headquarters and Headquarters Company, 191st Infantry Brigade, and assigned to the 96th Division. It was organized in December 1921 at Portland, Oregon, and redesignated on 23 March 1925 as Headquarters and Headquarters Company, 191st Brigade, then redesignated on 24 August 1936 as Headquarters and Headquarters Company, 191st Infantry Brigade. It was converted and redesignated on 6 April 1942 as the 96th Reconnaissance Troop (less 3rd Platoon), 96th Division (Headquarters and Headquarters Company, 192d Infantry Brigade, concurrently converted and redesignated as the 3rd Platoon, 96th Reconnaissance Troop, 96th Division). The Troop was ordered into active military service on 15 August 1942 and reorganize