During a reconnaissance mission to secure the construction of a railroad through the unceded territories of the Northern Plains, Lieutenant Colonel George Armstrong Custer and the United States 7th Cavalry encountered a group of Cheyenne and Lakota individuals near the Tongue River in Montana. This initial clash occurred as the cavalry aimed to protect a survey party assessing the feasibility of extending railroads into the region. The federal government sought to expand its infrastructure and control over the territories inhabited by Native American tribes, leading to increased tensions and conflicts over land rights and sovereignty.

On that fateful day, Custer's forces, numbering approximately 700 troops, engaged with an estimated 300 Cheyenne and Lakota warriors. Although the confrontation was brief, it was significant as it was the first battle between Custer’s 7th Cavalry and the indigenous tribes, symbolizing the escalating conflict over land and resources. The skirmish resulted in a single casualty for each side—one soldier and one Native warrior—which underscores the relatively limited scale of this initial engagement compared to subsequent battles in the American Indian Wars.

This encounter would pave the way for deeper conflicts in the years ahead, as tensions continued to rise between the expanding United States and the Native peoples resisting encroachment on their lands. Custer’s military approach and tactics would also be scrutinized in later, more intense engagements against the tribes that would follow, leading to a series of devastating conflicts resulting in the significant loss of life and land for Native Americans throughout the west.