In 1867, construction began by the 6th Cavalry on the 300-acre (120 ha) site along "Lost Creek, a small tributary of the West Fork of the Trinity River",[4] at a cost of $800,000, and occupied on 26 November.

"Originally a five-company post, it was expanded...to accommodate ten or more companies"[4] so that in 1872, with a population of 666 officers and men, it was listed as the largest U.S. Army installation in the United States.

Routine duties included long, arduous patrols along the frontier from Clay and Jack Counties west to Palo Duro Canyon near present-day Amarillo.

Battles with Comanche and Kiowa Indians became commonplace as the U.S. cavalry and infantry units sought to prove their ability to repel attacks and facilitate white settlement.

General Sherman arrived at Fort Sill and arrested Kiowa chiefs Satanta and Big Tree, and had them sent to Jacksboro to stand trial for their role in the massacre.

Following these events, General Sherman authorized the commander of the 4th Cavalry, Colonel Ranald S. Mackenzie, to begin offensive operations against the Comanche and Kiowa in the Texas Panhandle.

[9] Visitors can tour seven restored original buildings, including the post hospital, officers' quarters, powder magazine, morgue, commissary, guardhouse, and bakery.