The 415th Infantry was constituted in the Organized Reserve on 24 June 1921, assigned to the 104th Division, and allotted to the Ninth Corps Area. The regiment was initiated on 30 January 1922 with regimental headquarters organized at Casper, Wyoming. Subordinate battalion headquarters were concurrently organized as follows: 1st Battalion at Gillette, Wyoming; 2nd Battalion at Casper; and 3rd Battalion at Laramie, Wyoming. The regimental band was organized in 1923 at Roundup, Montana, and inactivated in 1929. The entire regiment was relocated on 2 May 1930 to Casper. The regiment conducted summer training most years with the 38th Infantry Regiment at Fort Douglas, Utah, and after 1927, with units of the 2nd Division's 4th Infantry Brigade at Fort D.A. Russell/Francis E. Warren, Wyoming, and the Pole Mountain Military Reservation, Wyoming. The primary ROTC
"feeder" school for new lieutenants for the regiment was the University of Wyoming. The regiment was inactivated on 27 December 1940 at Casper by relief of personnel.[1]
It was ordered into active service on 15 September 1942, and saw service during World War II with campaign participation credit for the Northern France, Rhineland, and Central Europe campaigns.
Service after the World Wars
Inactivated during post-World War II demobilization, the regiment was reactivated 12 June 1947 as part of the Organized Reserve and headquartered in Tacoma, Washington under the 104th Division. The Battalions have been realigned under the 95th Training Division and provides trained personnel to support Initial Entry Training. Most recently, the regiment have trained personnel ahead of deployments to the War in Afghanistan (2001-2021) and the War in Iraq (2003-2011).
Lineage
Constituted 24 June 1921 in the Organized Reserve as the 415th Infantry and assigned to the 104th Division (later redesignated as the 104th Infantry Division)
Organized in January 1922 with headquarters at Casper, Wyoming
Ordered into active military service 15 September 1942 and reorganized at Camp Adair, Oregon
^Clay, Steven E. (2010). U.S. Army Order of Battle, 1919-1941, Volume 1. The Arms: Major Commands and Infantry Organizations, 1919-41. Fort Leavenworth, KS: Combat Studies Institute Press. p. 505. This article incorporates text from this source, which is in the public domain.
^"PERMANENT ORDER 147-30"(PDF). history.army.mil/. US Army Center of Military History. 3 June 2010. Archived from the original(PDF) on 24 February 2014. Retrieved 3 June 2014.