The Battle of Blanco Canyon was the decisive battle of Col. Ranald S. Mackenzie's initial campaign against the Comanche in West Texas, and marked the first time the Comanches had been attacked in the heart of their homeland. It signified the end of Comanche control over the heart of their Comancheria, and the beginning of the end of the Comanche as a free people. In September 1871 Mackenzie received permission from Gen. William T. Sherman to begin an expedition against the Kotsoteka and Quahadi Comanche bands, both of whom had refused to relocate onto a reservation after the Warren Wagon Train Raid. Col. Mackenzie assembled a powerful force consisting of eight companies of the Fourth United States Cavalry, two companies of the Eleventh Infantry, and a group of twenty Tonkawa scouts.