The years and decades after the Civil War witnessed tremendous westward expansion — expansion that was fundamentally incompatible with the traditional lifestyle of the Indians. A final showdown was inevitable and it came in a series of Indian Wars between the so-called “hostiles” — tribes or tribal factions who resisted expropriation of their lands and refused to live on reservations — and the U.S. Army. Between 1865 and 1890, the Army battled many tribes in many places. It fought Apaches in the Southwest, Bannocks, Modocs, Utes and Nez Perce in the Northwest; and on the Plains, Kiowas, Comanches, Cheyennes, Arapahoes, and largest and most powerful of the Indian tribes, Sioux. With their superior horsemanship and knowledge of terrain, the Indians were not without victories. In 1868, Chief Red Cloud won his two-year campaign to oust the Army from forts along the Bozeman Trail, a route which passed through Sioux hunting grounds in the Powder River country of Wyoming. And, in 1876, Sioux and Cheyenne warriors defeated U.S. troops in battles at the Rosebud and the famous Little Big Horn. But in the end, the Army — superior in numbers and technology — prevailed, aided in part by the destruction of the buffalo, the Plains Indians’ primary source of food.

African-Americans were active participants on the western frontier, particularly in the years after the Civil War. Many cowboys were black, skilled as cowhands, horsebreakers and riders on the long drive. Although the top jobs of trail boss and ranch foreman were closed to them, blacks often filled the next most authoritative position — the chuckwagon or ranch cook. Blacks also homesteaded. In the late 1870s, tens of thousands of black “Exodusters” fled the poverty and discrimination of the post-Reconstruction South to found farming communities in Kansas, such as Nicodemus. And blacks served with distinction in the Indian Wars of 1865-1890. Two cavalry regiments (the Ninth and Tenth) and two infantry regiments (the Twenty-Fourth and Twenty-Fifth) of the U.S. Army were composed of blacks, under white officers. These “buffalo soldiers” — as the Indians called them because of the texture of their hair — fought in numerous engagements against Cheyenne, Comanche, Kiowa, Apache, Ute and Sioux warriors, several times coming to the aid of beleaguered white troops. they also took part in patrolling the disquiet Texas-Mexican border and staffed the garrisons of many frontier posts. Between 1870 and 1890, 14 black soldiers were awarded the Congressional Medal of Honor for bravery as were four black Army scouts.

Although the East was the main theater of the Civil War, there were battles in the West as well. In 1862, Union forces defeated Texas troops at La Glorietta Pass, New Mexico, forcing the Confederates to withdraw from the New Mexico Territory. But it was not the conflict between North and South that produced most of the bloodshed in the West during this time. It was the clash between Indians and whites. The withdrawal of federal garrisons at the outbreak of the Civil War, together with the provocation of white encroachment, produced a rash of Indian uprisings. In the Southwest, the Apaches and Navajos raided frontier settlements until subdued and relocated by volunteers under Gen. James Carleton and Col. Kit Carson (1862-1864). Carson also led the 1864 campaign to halt Kiowa and Comanche attacks on the Santa Fe trail. In 1862 the Santee Sioux of Minnesota killed more than 600 settlers, after federal Indian agencies had failed to pay “annuities” due and needed for food. The Santee were captured, punished and removed from Minnesota to the Dakota Territory. Hostilities in Colorado led to one of the worst atrocities by whites — the San Creek Massacre of 1864. Promised military protection, chief black Kettle’s Cheyenne and Arapahoe encampment was attacked instead by Col. John Chivington’s Colorado volunteers. After the Civil War ended, the Indian Wars only intensified.