Unlike the flashy and self-promoting George Armstrong Custer, Civil War veteran and Indian fighter Ranald Slidell Mackenzie is not well known today. In the late nineteenth century, however, Mackenzie ranked among the best known and most effective of a group of young army colonels who led in the defeat of the Plains Indians and the opening of the West to white settlement, as Michael D. Pierce shows in this compelling and poignant biography.

A rather shy and sometimes distant personality, Mackenzie, following his graduation from West Point in 1862, showed early promise in...