The first U.S. soldiers entered Utah territory in 1858 as part of the infamous Utah War. Those troops established Camp Floyd in what is now Fairfield. The "war," in which neither side fired a shot at their adversaries (although the Mormon Militia did harass supply trains, steal cattle and such), pretty much ended in a stalemate when the Civil War broke out and about half the officers left to join the Confederacy.

But a military presence would remain in the area for generations to come. During the Civil War, Col. Patrick E. Connor and his California-Nevada volunteers were sent to the Utah Territory to guard the Overland Mail Route from Indian or other attack. Connor, an Irish emigrant with a hearty dislike for the Mormons, also planned to keep an eye on them, and thus chose a site on the east bench overlooking the valley for his headquarters. The post was named Camp Douglas, in honor of the recently deceased senator from Illinois, Stephen A. Douglas, who had been a supporter of the West.

Connor spent his time with military activities, but he also sent men into the mountains to prospect for gold and silver.

By 1866, Connor's volunteers had been discharged and replaced by regulars from the 18th Infantry. But by the end of the decade, the distrust between the settlers and the army evolved into wary acceptance of each other. The Mormons had remained loyal to the Union; the army presence was an economic boon to the valley.

During the 1870s, Camp Douglas became increasingly important as a cavalry supply center, and what was planned as a temporary outpost became a permanent Fort Douglas.

As the Indian wars ended toward the end of the century, conflict with Spain increased. The 24th Division, known as the Buffalo Soldiers, which had been stationed at the fort, departed for action in Cuba.

In 1901, Fort Douglas was upgraded to a regimental headquarters whose duties included training of troops for other service. In 1913, the fort's 20th Infantry participated in the chase of Pancho Villa into Mexico.

During World War I, Fort Douglas was used as a training base, mobilization and separation center, general hospital and POW camp. In 1922, it became home to the 38th Infantry, also known as the "Rock of the Marne."

After the attack on Pearl Harbor, the 9th Service Command moved from the Presidio of San Francisco to Fort Douglas in fear of a Japanese attack on the West coast.

Over the years, the original size of the fort diminished from 10,525 acres to the present 58 acres as land was carved away for Mt. Olivet Cemetery, the University of Utah, This Is the Place Monument, Shriners Hospital for Children, the Veterans Medical Center and more.

Proposed closure of the post cropped up quite regularly: in the 1860s, before World War I, after World War II, in 1967 and in 1978. Finally, in 1991, federal legislation transferred 51 acres to the University of Utah in exchange for state lands. The southern portion of the base became the headquarters of the 96th Army Reserve Command and is used as a base of operation for U.S. Navy and Marine Reserves.