The term refers to the defeat of General George A. Custer (1839–1876) at the Battle of Little Bighorn on June 25, 1876. Custer had a national reputation as a Civil War general and Indian fighter in the west, and when he and his troops were outnumbered and badly beaten by the Sioux led by Sitting Bull (c. 1831–1890)—just as the country was about to celebrate the hundredth anniversary of the Declaration of Independence—the result was a stunning reversal in the national mood.

Little Bighorn was part of a series of campaigns known collectively as the Sioux War. Several events led to the conflict that became Custer’s Last Stand. The Sioux were nontreaty Indians, which means they had refused to accept the white-dictated limits on their territory. They were outraged at the repeated violation of their lands by the onrush of miners to new gold strikes in the Black Hills of South Dakota. Further, there had been eight attacks by the Sioux on the Crow who were living on reservation land. Finally, Sitting Bull, the chief of the Hunkpapa band of Sioux, refused government demands that he and his people return to reservation lands. Meanwhile, unbeknownst to the government’s military strategists, by spring 1876 Sitting Bull had been joined in his cause by other groups of northern Plains tribes, including the Cheyenne led by Crazy Horse (c. 1842–1877). With the government ready to use force to return Sitting Bull and his band of Sioux to reservations, the stage was set for a conflict—bigger than any Washington official had imagined.

On June 25 Custer rode into Montana territory with his Seventh Cavalry to meet the Sioux. Despite orders to simply contain the Indians and prevent their escape, he attacked. While historians remain divided on how Custer could have been defeated on that fateful June day, one thing remains certain: Custer and his men were badly outnumbered. Having divided his regiment into three parts, Custer rode with about 225 men against a force of at least 2,000—the largest gathering of Indian warriors in Western history. Custer and his soldiers all died. The fighting continued into the next day, with those Indians that remained finally disbanding and returning to their designated territory. Meantime, Sitting Bull and his band retreated into Canada. Returning to the United States five years later, in 1890, Sitting Bull was killed by authorities.

The battle became the subject of countless movies, books, and songs. It’s remembered by some Native Americans as a galvanizing force—proof that brave men who fight for what they believe in can win.