Fort Pease

By editor

Hysham, Treasure County, Montana

In the summer of 1875, amidst the sprawling plains and rugged river valleys of the northern Yellowstone region, a modest military and trading post was established that would come to bear witness to the turbulent struggles of the American frontier. Fort Pease, founded in June of that year a few miles below the mouth of the Bighorn River, was the brainchild of enterprising businessmen from Bozeman who sought to capitalize on the promise of steamboat navigation along the Yellowstone River. Their hope was that the fort would serve as a terminus for river commerce, a gateway to the wealth and settlement of the region. Yet, the enterprise was ill-conceived, for the fort occupied lands held sacred and long favored for hunting by the Lakota Sioux and their allied tribes, whose dominion over these plains was still vibrant and fiercely defended.

The decision to build Fort Pease on such contested ground was fraught with peril from the outset. The winter of 1875-76 proved a grim season for the fort’s occupants. The Lakota, under the leadership of formidable war chiefs such as Sitting Bull and Crazy Horse, regarded the growing presence of settlers, trappers, and soldiers as encroachments upon their territory. Harassment of the fort’s inhabitants was relentless. Trappers working the surrounding lands reported constant threats, and the toll was grievous: six were killed and eight wounded during those bitter months. The small garrison and civilian workers found themselves beleaguered, their isolation compounded by the harsh Montana winter. The situation deteriorated to the point that the trappers dispatched urgent appeals for military aid to Fort Ellis, near Bozeman, some 150 miles to the west.

In early March of 1876, relief arrived under the command of Major James S. Brisbin, a veteran officer of the Second Cavalry, accompanied by four companies dispatched from Fort Ellis. Brisbin’s orders were clear, though tempered by prudence: while the Lakota had not been sighted in the immediate vicinity for nearly a month and the trappers had resumed their labors, the danger remained palpable. The Major was instructed not merely to reinforce the fort but to withdraw the trappers to the relative safety of Fort Ellis. This course reflected the broader strategic uncertainty gripping the region, as the federal government and military commanders sought to assert control over the Plains tribes even as hostilities intensified.

Two days following the arrival of the cavalry, Brisbin and the trappers commenced their westward march, abandoning Fort Pease. They left the fort intact, though many expected the Lakota to destroy the empty post upon discovering it deserted. The assumption proved mistaken. On April 19, 1876, Colonel John Gibbon arrived at Fort Pease with the Montana Column, a contingent assembled to join the wider military campaign against the Plains tribes. To the surprise of Gibbon’s men, the fort remained virtually untouched, the American flag still flying above its walls, and a solitary dog greeted the troops at the gate. This scene of abandonment and preservation encapsulated the uncertainty and flux that characterized the military operations on the northern plains at that moment.

Colonel Gibbon’s arrival occurred against the backdrop of mounting conflict that would soon erupt in the infamous Battle of the Little Bighorn. On the day following his arrival at Fort Pease, Gibbon received dispatches from General Alfred Terry, ordering him to continue patrolling the north side of the Yellowstone River to prevent any movement of Indian forces across the river. Gibbon took command of the fort for two weeks, during which he dispatched scouting parties along the Yellowstone and as far south as Bighorn Canyon, endeavoring to gather intelligence and assert federal presence in a region where the balance of power remained contested.

The military importance of Fort Pease lay not only in its geographic location near the confluence of the Bighorn and Yellowstone Rivers but also in its role as a staging ground and supply depot during one of the most critical campaigns in the Plains Indian Wars. After the catastrophic defeat suffered by Lieutenant Colonel George Armstrong Custer and the Seventh Cavalry at the Battle of the Little Bighorn on June 25-26, 1876, Fort Pease became a rallying point. The Montana Column, along with the battered remnants of the Seventh Cavalry, regrouped at the fort, awaiting reinforcements and supplies. The delay was painful, for the soldiers and officers were acutely aware of the precariousness of their situation. Colonel Gibbon, writing in the months following the campaign, reflected on the fort’s role: "We held Fort Pease as a bastion against the forces arrayed against us, knowing that the vastness of the plains and the tenacity of our adversaries demanded every ounce of vigilance and resolve."

Yet, despite its temporary significance, Fort Pease was ultimately a way station rather than a lasting installation. The military soon determined that a more strategically advantageous site was needed to maintain control over the region and to support ongoing campaigns against the Plains tribes. This led to the selection of a cantonment at the confluence of the Tongue River, where construction of Fort Keogh commenced in early 1877 under orders from the War Department. Fort Keogh would soon eclipse Fort Pease in military importance, serving as a critical base for the consolidation of federal authority throughout eastern Montana and northern Wyoming.

The fate of Fort Pease mirrors the broader narrative of westward expansion and conflict in the late nineteenth century. Established on speculative economic hopes that failed to materialize, built atop land fiercely contested by indigenous peoples, and caught in the turbulent currents of imperial contest, the fort’s brief existence was marked by hardship and strategic recalibration. It witnessed the ebb and flow of military fortunes and the grim realities of a frontier carved by violence and ambition.

In the end, Fort Pease remains a quiet landmark in Montana’s history--a place where commerce, military necessity, and native resistance intersected with profound consequences. Its story is preserved not only in the worn timbers and scattered ruins but in the dispatches and memoirs of those who lived through its brief but eventful existence. Such was the fate of many frontier outposts, whose transient nature belied their role in shaping the destiny of the American West.

See also

• Fort Pease at Hysham, Treasure County
• Captain Ball's Scout at Crow Agency, Big Horn County
• Custer Campsite -- June 22, 1876 at Rosebud, Rosebud County