The document discusses the removal of Native Americans from the Great Plains in the late 19th century. Railroads helped speed western expansion by transporting settlers and soldiers and improving communication. The Plains Indians like the Sioux and Comanche were nomadic peoples who followed buffalo herds. Railroads cut the buffalo's migratory paths, reducing the buffalo population and threatening the Plains Indians' main resource. As settlers moved in, US policy changed to relocating Indians to reservations, which were incompatible with their nomadic lifestyle. The Dawes Act broke up tribal lands and allotted individual families small farms, but failed because Plains Indians were hunters unaccustomed to farming and the concept of land ownership.