When the Wolf Came is a deeply researched and engagingly corrective addition to the sparse or dated existing studies of a critical period in the history of the Indian Territory; it is especially valuable for its extensive incorporation of the perspectives of those inside rather than outside the Territory. Occupying the intersection between the history of the Civil War and of the American West, it deserves careful reading by military historians interested in irregular warfare and students of the history of the United States generally and Oklahoma in particular.