The Camp on Pawnee Fork was established on October 22, 1859, to protect traffic along the Santa Fe Trail from hostile Native Americans.

As the American government claimed vast amounts of land west of the Mississippi River, trade and commerce with the territories grew exponentially.

In August, 1861, Colonel Leavenworth, reporting from Fort Larned, stated the Indians had left the Santa Fe trail area and there was no apprehension of any hostilities.

Soldiers in the regular army were removed from the post to join the growing conflict in the East, leaving the fort to be operated by volunteer troops from Kansas, Colorado, and Wisconsin.

In May 1862, Confederate General Albert Pike arranged an alliance with some Kiowa and Seminole Indians with intentions of capturing Forts Larned and Wise.

After the meeting, Hancock, along with George Armstrong Custer and the 7th U.S. Cavalry traveled west of Fort Larned to a combined Cheyenne and Lakota camp, inciting the villagers to flee.

Fort Larned assisted in bringing Hancock's War to an end by supplying the Medicine Lodge Treaty.

[4] During the winter of 1868–69, U.S. Major General Philip H. Sheridan launched a campaign against the Cheyenne, Kiowa, and Comanche Indians in the Great Plains region.

Sheridan's men attacked any who resisted, taking their supplies and livestock and pushing the remaining Indians back into their reservations.

By the end of the Winter Campaign, Sheridan had forced a majority of the Indians in the Fort Larned area on to reservations.

The original sod and adobe structures were removed and replaced with the sandstone buildings that make up the fort today.

By 1871, no escorts were required for the wagon trains traveling on the Santa Fe Trail, eliminating the need for military presence in the region.

Warehouses – An important role for a frontier fort was as a place to store the supplies that kept the Army functioning, including food, ammunition, and clothing.

The first two, the Old Commissary and the Quartermaster Storehouse, brandish loopholes from which the fort could be defended with rifle fire in the event of an attack.

The fire killed dozens of horses, destroyed equipment, and caused the unit to be reassigned to Fort Zarah.