It lasted less than an hour. In that short span of time on June 25, 1876, Lt. Col. George Armstrong Custer and more than 260 of his men were killed along the banks of the Little Bighorn River in present-day Montana, dealt a stunning defeat by a coalition of Lakota Sioux, Northern Cheyenne, and Arapaho warriors. The Battle of Little Bighorn remains one of the most written-about, debated, and mythologized military engagements in American history. But beneath the legend lies a story of broken treaties, Indigenous resistance, and the brutal collision of two worlds.