Hualapai War

 (1866-1870) - Started in 1866 as a conflict between Hualapai Indians of present day northwest Arizona and the U.S. Army over attacks on settlers and travelers. The turning point came with the Battle of Battle of Cherum Peak in January 1868. Hualapai losses and an outbreak of dysentery and whooping cough caused many of the Hualapai Indians to surrender and the war finally ended in 1870. It has been estimated that 1/3 of Hualapai population was lost in the conflict.

Links:
 * Wikipedia - Hualapai War