Utah's first militia was called the Nauvoo Legion after a similar organization in Illinois. Abolished by the Edmunds-Tucker Act in l887, the militia was revived in 1894 as the Utah National Guard. The state established a camp for the guard in 1928, named in honor of Brigadier General W. G. Williams. The guard has participated in aspects of every war since the Spanish-American War, including island-hopping in the Pacific and invading Europe during World War II. Camp Williams also became a sub-post and training site for Fort Douglas during World War II. Prior to the Korean War, the state stationed three Air National Guard units at the Salt Lake Airport.

Hill Air Force Base in Davis County, formerly home of the Ogden Air Material Area (OOAMA), and now a unit of the Air Logistics Command is home base for several airplane units and provides technical and logistical support for Air Force units in nearly all the western states. The initial construction of Hill Air Force Base was completed in November 1939. During World War II, OOAMA's duties consisted primarily of supplying, storing, repairing, and maintaining aircraft. During the postwar period, OOAMA performed similar services during the Berlin Airlift and the Korean and Vietnam wars. By 1960, OOAMA was a world-wide manager for air munitions and explosives. Under the Air Force Logistic Command its duties now include responsibility for the F-l6. It remains today an important link in the Air Force's space-age technology. Hill is the largest single employer in the state.