The 1874 founding and the Cheyenne-Arapaho Reservation era
Fort Reno was established in July 1874 by the U.S. Army's 10th Infantry on the south bank of the North Canadian River, on a site selected for its proximity to the Darlington Agency — the Bureau of Indian Affairs headquarters for the Cheyenne and Arapaho Reservation, located about 5 miles north across the river. The reservation itself had been created in 1869 and covered roughly 4.3 million acres of western Indian Territory; Fort Reno's primary mission was to maintain order on and around this reservation during a period of substantial tension between the tribes, federal Indian agents, and the steady pressure from white settlers and cattle ranchers along the reservation's boundaries.
The fort was named for Major General Jesse L. Reno, a Union officer killed at the Battle of South Mountain in 1862. Initial construction was hasty — tent encampments and rough frame structures — but by 1876 the post had developed a substantial cantonment with officers' quarters, barracks, stables, a hospital, a chapel, and the headquarters building that still stands today and houses the visitor center. The 4th Cavalry was the primary garrisoning unit through the 1870s and 1880s, with regular rotations of infantry companies cycling through.
Cavalry units from Fort Reno participated in the Red River War of 1874-75 (the final major Indian War campaign on the southern Plains, ending with the surrender of Comanche, Kiowa, and Cheyenne bands at Fort Sill), various smaller campaigns through the 1880s, and the Ghost Dance disturbances of 1890-91. The fort was also the staging area for the Buffalo Soldiers of the 9th and 10th Cavalry during multiple deployments, and several Buffalo Soldier graves remain in the post cemetery today.