The allied Lakota and Arapaho bands and the unified Northern Cheyenne were involved in much of the warfare after 1860. They fought a successful delaying action against General George Crook's army at the Battle of the Rosebud, preventing Crook from locating and attacking their camp, and a week later defeated the U.S. 7th Cavalry in 1876 at the Battle of the Greasy Grass in the Crow Indian Reservation of 1868. Custer attacked a camp of several tribes, much larger than he realized. Their combined forces, led by Chief Crazy Horse, killed 258 soldiers, wiping out the entire Custer battalion in the Battle of the Little Bighorn, and inflicting more than 50% casualties on the regiment.