Robert M. Utley is a preeminent historian of the West and the author of numerous award-winning books, including The Last Days of the Sioux Nation; Frontiersmen in Blue: The United States Army and the Indian, 1848–1865 (Nebraska, 1981); Custer and the Great Controversy: The Origin and Development of a Legend (Nebraska, 1998); and Frontier Regulars: The United States Army and the Indian, 1866–1891 (Bison Books, 1984).