Crazy Horse was a Lakota war leader of the Oglala band in the 19th century who fought against the United States federal government to preserve the traditional way of life of the Lakota people and to fight against encroachment by white American settlers on Native American territory. He was born in or near the Black Hills of South Dakota, probably in 1840, to parents from two different bands of the Lakota division of the Sioux. His father was also named Tȟašúŋke Witkó (Crazy Horse) . Crazy Horse was named Čháŋ Óhaŋ (Among the Trees) at birth, and his mother gave him the nickname Pȟehíŋ Yuȟáȟa (Curly Son/Curly) or Žiží (Light Hair) as his light, curly hair resembled her own.

Crazy Horse was a skilled warrior and a leader in his peoples defiance of U.S. plans to construct a road to the goldfields in Montana. He participated in several famous battles, including the massacre of Captain William J. Fetterman and his troop of 80 men and the Wagon Box fight, both near Fort Phil Kearny, in Wyoming Territory. He was pursued by Colonel Nelson A. Miles in a stepped-up army campaign to force all Native Americans to come to the government agencies. His tribe weakened by cold and hunger, Crazy Horse finally surrendered to General Crook at the Red Cloud Agency in Nebraska on May 6, 1877. Confined to Fort Robinson, he was killed in a scuffle with soldiers who were trying to imprison him in a guardhouse.

Crazy Horse is commemorated by the incomplete Crazy Horse Memorial in the Black Hills of South Dakota, near the town of Berne. The sculpture was begun by Polish-American sculptor Korczak Ziółkowski, who had worked under Gutzon Borglum on Mount Rushmore, in 1948. Plans call for the completed monument to be 641 feet (195 m) wide and 563 feet (172 m) high.