Center for Army Lessons Learned - Thesaurus
CALL title banner

40th Infantry Division (Mechanized) (ARNG)

Definition/Scope: The 40th Infantry Division (40th ID) was activated on 18 July 1917 (National Guard Division from California, Nevada, and Utah). They were sent overseas on 3 August 1918 and redesignated to the 6th Depot Division which they then received, equipped, trained, and forwarded replacements. They returned to U. S. on 30 June 1919 and deactivated. They were reactivated on 3 March 1941 (National Guard Division from California and Utah) and transferred to Hawaii on 23 August 1942. They returned to U. S. on 7 April 1946 and deactivated once again on 7 April 1946. The 40th Infantry Division’s first oversea assignment was the defense of outer islands of Hawaii, where it arrived in September 1942. Training continued as defensive positions were improved and maintained. In July 1943 the Division was concentrated on Oahu, and relieved the 24th of the defense of the North Sector. They were relieved of the North Sector in October 1943, the 40th entered upon a period of amphibious and jungle training. On 20 December 1943, the first units left for Guadalcanal, and by mid-January 1944, movement was completed, and the Division prepared for its first combat assignment. On 24 April 1944, it left Guadalcanal for New Britain. The 40th was relieved of missions on New Britain, 27 November, and began training for the Luzon landing. Sailing from Borgen Bay, 9 December 1944, the Division made an assault landing at Lingayen, Luzon, under command of XIV Corps, on 9 January 1945. In September 1945, the Division moved to Korea for occupation duty. On 01 September, 1950, the 40th Infantry Division was mobilized and moved to Camp Cooke, California. After some initial training and reception of fillers, the division was shipped to Japan the following spring for advanced training. The division was committed across the Sea of Japan, landing at Inchon to relieve the 24th Infantry Division in January and February of 1952. The 40th Infantry Division (US) was relieved from active Federal service on June 30, 1954, and reverted to state control. The next day the division was reorganized and redesignated the 40th Armored Division. On 1 December 1967, a major reorganization of the National Guard reduced the Guard to eight combat divisions, the 40th Armored Division being one of the reductions. On 29 January 1968, the Division was eliminated and the 40th Infantry Brigade and 40th Armored Brigade were organized. On 13 January 1974, the California Army National Guard was reorganized. The 40th and 49th Infantry and the 40th Armored Brigades were deactivated and the 40th Infantry Division was reformed. The 40th ID has the following subordinate units: 1st Infantry Bde, 2nd Armored Bde, 3rd Armored Bde, Div Artillery, 40th Aviation Bde, 40th Engineer Bde, and the Div Support Command.


40th ID(M)

Broader Terms:

ARNG Infantry divisions
California Army National Guard

Related Terms:

Fighting Fortieth

CALL Homepage >> Thesaurus Last Updated: Sept 17, 2008