The Texas Rangers earned the condemnatory nickname Los Diablos Tejanos (the Texas Devils) during the Mexican-American War because of their brutality toward civilians as well as the Mexican military. Their cruel conduct even disgusted Gen. Zachary Taylor, who sent them packing as soon as possible. Never forgetting the atrocities of the Mexican Army at the Alamo and Goliad in the Texas Revolution of 1836, the Rangers persisted in their vengeful, oppressive conduct toward Mexicans. Collins’ focus is on the lower Rio Grande in the years between the Mexican and Civil Wars. His theme is not so much Ranger bigotry against Mexican bandidos, but the Rangers’ campaigns against Comanches in Texas and other hostiles along the border. The great exception is Juan Cortina, who symbolized Mexican resistance to the Rangers. Collins tells the story well, but for the best accounts of the Cortina Wars, read also Jerry Thompson’s Juan Cortina (1994) and his Cortina (2007).