In 1874, in direct violation of the treaty, General George A. Custer and his 7th Cavalry entered the Black Hills and discovered gold, starting a gold rush. The United States government wanted to buy or rent the Black Hills from the Lakota people, but led by their spiritual leader Sitting Bull, they refused to sell or rent their lands. The Great Sioux War of 1876 was a series of battles and negotiations that occurred between 1876 and 1877, with the Lakota Sioux and Northern Cheyenne warring against the United States. Among the many battles and skirmishes of the war was the Battle of the Little Bighorn, often known as Custer's Last Stand, the most storied of the many encounters between the U.S. army and mounted Plains Native Americans. It was an overwhelming Native American victory. The U.S. with its superior resources was soon able to force the Native Americans to surrender, primarily by attacking and destroying their encampments and property. The Agreement of 1877 (19 Stat. 254, enacted February 28, 1877) officially annexed Sioux land and permanently established Native American reservations. Under the Agreement of 1877 the U.S. government took the Black Hills from the Sioux Nation.