171st Infantry Brigade (United States)

171st Infantry Brigade
171st Infantry Brigade shoulder sleeve insignia
Active	1917–1946 1963–1972 2007–present
Country	United States
Branch	United States Army
Type	Infantry
Role	Training support
Size	Brigade
Garrison/HQ	Fort Jackson, South Carolina

The 171st Infantry Brigade was an infantry brigade of the United States Army based at Fort Jackson, South Carolina. With a long history of serving, the brigade saw action during both World War I and World War II before it was inactivated in 1946. During the Cold War (in 1963) the brigade was once again activated for a period of ten years until again inactivated in 1972. In 2007 the brigade was reactivated as a training support unit and inactivated on June 10, 2016.

Constituted 5 August 1917 in the National Army as Headquarters, 171st Infantry Brigade, and assigned to the 86th Division. Organized 3 September 1917 at Camp Grant in Rockford, Illinois. Demobilized in January 1919 at Camp Grant, Illinois. Reconstituted 24 June 1921 in the Organized Reserves as Headquarters and headquarters Company, 171st Infantry Brigade, and assigned to the 86th Division. organized in July 1922 at Chicago, Illinois. Redesignated 23 March 1925 as Headquarters and Headquarters Company, 171st Brigade. Redesignated 24 August 1936 as Headquarters and Headquarters Company, 171st Infantry Brigade.

Converted and redesignated 31 March 1942 as the 86th Reconnaissance Troop (less 3d Platoon), 86th Division (Headquarters and Headquarters Company, 172d Infantry Brigade, concurrently converted and redesignated as the 3d Platoon, 86th Reconnaissance Troop, 86th Division). Troop ordered into active military service 15 December 1942 and reorganized at Camp Howze, Texas, as the 86th Cavalry Reconnaissance Troop, an element of the 86th Infantry Division. Reorganized and redesignated 5 August 1943 as the 86th Reconnaissance Troop, Mechanized. Reorganized and redesignated 10 October 1945 as the 86th Mechanized Reconnaissance Troop. Inactivated 30 December 1946 in the Philippine Islands. (Organized Reserves redesignated 25 March 1948 as the Organized Reserve Corps; redesignated 9 July 1952 as the Army Reserve.)

Converted and redesignated (less 3d Platoon) 20 May 1963 as Headquarters and Headquarters Company, 171st Infantry Brigade, and relieved from assignment to the 86th Infantry Division; concurrently withdrawn from the Army Reserve and allotted to the Regular Army (3d Platoon, 86th Reconnaissance Troop – hereafter separate lineage). Brigade activated 1 July 1963 at Fort Wainwright in Fairbanks, Alaska. Inactivated 13 November 1972 in Alaska.