The Bannock War of 1878 was an armed conflict between the U.S. military and Bannock and Paiute warriors in Southern Idaho and Northern Nevada, lasting from June to August 1878. The Bannock-Paiute totaled about 500 warriors; they were led by Chief Buffalo Horn who was killed in action in June. After his death, Chief Egan led the Bannock. He and some of his warriors were killed in July, by an Umatilla party who entered his camp in subterfuge. The U.S.