On Sunday afternoon, June 25, 1876, Gen. George Custer and 264 members of the U.S. Seventh Cavalry engaged more than 3,000 warriors of the Lakota Sioux, Arapaho, and Cheyenne nations and were killed in the ensuing battle. Acclaimed historian Dee Brown traces the events of that day and of the weeks before, through the eyes and ears of seventeen participants from both sides, including Natives, scouts, soldiers, and civilians. Why did Custer...