At the end of the Ice Age, about 9000 years ago, people hunted wooly mammoths and ancient bison on the plains of what is now Kansas using spears and atlatls and making stone points from native flint, while living as migrants rather than in permanent settlements. About 2200 years ago, ancestors of the modern Pawnee Indians moved from the eastern woodlands onto the plains and into the river valleys of western Kansas, bringing bows and arrows, pottery, and farming knowledge, while also following buffalo, building earth lodges, and growing crops. By 1500, Atapaskan people, called Apaches by the Spanish, had moved into western Kansas, where they hunted, farmed to a lesser extent, and held many natural places sacred, as Kansas was truly home to native peoples rather than merely a hunting ground. The Comanche, among the first Indians of the central plains and Rockies to master the horse, had moved into what is now Kansas by 1706 and conquered or drove out the Apaches, earning the name Lords of the Plains through their rule of the prairie buffalo country, but by 1800 their dominance in western Kansas was challenged by the Sioux, Arapaho, and especially the Cheyenne. After 1830, when the U.S. Congress passed the Indian Removal Act, the government forced Indian people in eastern states to surrender their lands for territory beyond the Missouri River, bringing Shawnee, Kickapoo, Delaware, Miami, Ottawa, and other tribes into competition for resources in Kansas. The Kansas-Nebraska Act of 1854 opened Kansas to white settlement, and although the government tried to make treaties with most tribes, many native people resisted giving up their homes. In 1857, General Edwin V. Sumner led the first military expedition against Indians in western Kansas in response to Comanche raids, and after Colonel John Chivington led the brutal massacre of a peaceful Cheyenne camp at Sand Creek in nearby Colorado, warfare spread across the central plains. The army then established forts including Fort Hays in 1865 and Fort Wallace, Colonel George A. Custer campaigned in the region in 1867 and 1868, and scouts including Buffalo Bill Cody, Wild Bill Hickok, and Medicine Bill Comstock guided cavalry expeditions through the Smoky Hill country. After the Civil War, many tribes in Kansas were forced to move again to Indian Territory, and after fifteen years of repeated hostilities in the Smoky Hill region, chiefs Little Wolf and Dull Knife led a final Cheyenne escape from captivity in Indian Territory toward their northern plains homelands, passing through what is now Logan County while eluding the cavalry; though not bloodless, the trek drew admiration from some in the eastern press and closed a dramatic chapter in the taming of the American west.