Sitting Bull did not agree to the treaty. He told the Jesuit missionary, Pierre Jean De Smet, who sought him out on behalf of the government: "I wish all to know that I do not propose to sell any part of my country." He continued his hit-and-run attacks on forts in the upper Missouri area throughout the late 1860s and early 1870s. The events of 1866–1868 mark a historically debated period of Sitting Bull's life. According to historian Stanley Vestal, who conducted interviews with surviving Hunkpapa in 1930, Sitting Bull was made "Supreme Chief of the whole Sioux Nation" at this time.
Sitting Bull the Cheyenne during the Plains Wars because they thought the other nation was under attack by the US. Given this connection, she suggests the major war should have been called "The Great Cheyenne War". Since 1860, the Northern Cheyenne had led several battles among the Plains Indians. Before 1876, the U.S. Army had destroyed seven Cheyenne camps, more than those of any other nation. Other historians, such as Robert M. Utley and Jerome Greene, also use Lakota oral testimony, but they have concluded that the Lakota coalition, of which Sitting Bull was the ostensible head, was the primary target of