The 40th Infantry Division ("Sunburst Division") is a modular division of the United States Army. Following the army's modularization the division has become a four-brigade combat team with National Guardsmen from throughout the Pacific/Western United States and Oceania. Its division headquarters is located at Los Alamitos Joint Forces Training Base in Los Alamitos, California.
After seeing service in World War I as a depot division, it was reorganized as the National Guard division for California, Nevada, and Utah, before seeing service in the Pacific Theatre of World War II. Later, the division served in Korea and some of its units were designated for Vietnam. The division was later reorganized redesigned as a National Guard unit completely within California. Later reorganizations included units from other states. As currently configured, the 40th Infantry Division has oversight and responsibility for the training and readiness of units in California, Oregon, Hawaii, Arizona, Washington, Alaska, New Mexico, Indiana, Nebraska, Nevada, Mississippi, Utah, Guam, and the Northern Mariana Islands.
Service record
Constituted on 18 July 1917 following the American entry into World War I, the 40th Infantry Division was organized at Camp Kearny, near San Diego, California, on 16 September, originally designated as the 19th Division. It was composed of National Guard units from the states of Arizona, California, Colorado, Nevada, New Mexico, and Utah.
World War I
It was sent overseas on 3 August 1918 and redesignated as the 6th Depot Division; received, equipped, trained, and forwarded replacements. Major General Frederick S. Strong was assigned as commander on 25 August 1917, but was replaced less than a month later by Brigadier General G. H. Cameron on 18 September 1917.
The division then saw a rapid turnover of leaders – Brigadier General L. S. Lyon (19 November 1917), Brigadier General G. H. Cameron (23 November 1917), Brigadier General L. S. Lyon (6 December 1917) and then Major General F. S. Strong again on 8 December 1917.
Order of battle
Headquarters, 40th Division
79th Infantry Brigade
157th Infantry Regiment (former 1st Colorado Infantry, and 1st Colorado Cavalry less band and Troop E) 158th Infantry Regiment (former 1st Arizona Infantry) 144th Machine Gun Battalion (former 3rd Battalion and Machine Gun Company, 1st New Mexico Infantry) 80th Infantry Brigade 159th Infantry Regiment (former 5th California Infantry, and 2nd California Infantry less band, 2nd Battalion, and Companies L and M) 160th Infantry Regiment (former 7th California Infantry, and 2nd Battalion and Companies L and M, 2nd California Infantry) 145th Machine Gun Battalion (former Troops A, B, and C and Machine Gun Troop, 1st Separate Squadron California Cavalry) 65th Field Artillery Brigade 143rd Field Artillery Regiment (75 mm) (former 1st California Field Artillery) 144th Field Artillery Regiment (155 mm) (former 2nd California Field Artillery) 145th Field Artillery Regiment (4.7") (former 1st Utah Field Artillery) 115th Trench Mortar Battery (former Machine Gun Company, 2nd Colorado Infantry) 143rd Machine Gun Battalion (former 1st and 2nd Battalions, 1st New Mexico Infantry) 115th Engineer Regiment (former 1st Battalion, Colorado Engineers, and Troop E, 1st Colorado Cavalry) 115th Field Signal Battalion (former Company B, California Signal Corps and Company B, Colorado Signal Corps) Headquarters Troop, 40th Division (former Troop D, 1st California Cavalry) 115th Train Headquarters and Military Police (former Headquarters, Headquarters Company less band, and Supply Company, 1st New Mexico Infantry) 115th Ammunition Train (former Headquarters, Headquarters Company less band, and 2nd and 3rd Battalions, 1st Colorado Infantry) 115th Supply Train (former Supply Company and 1st Battalion, 1st Colorado Infantry) 115th Engineer Train (former 1st Colorado Engineer Train) 115th Sanitary Train 157th, 158th, 159th, and 160th Ambulance Companies and Field Hospitals (former California Ambulance Companies No. 1 and 2 and Field Hospital Companies No. 1 and 2, and Utah Field Hospital No. 1)