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What happened during the Fetterman Massacre in 1866?

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A Cheyenne River Sioux dancer in colorful traditional regalia performs during the Grand Entry at a powwow, with an American flag and other participants in the background. — Oceti Sakowin A member of the Cheyenne River Sioux Tribe performing during the Grand Entry at the Cheyenne River Sioux Tribe Fair Rodeo and Powwow, Eagle Butte, South Dakota, September 4, 2016.

In December 1866, during the conflict known as Red Cloud’s War, warriors from the Oceti Sakowin (Lakota) successfully executed an ambush against a U.S. military patrol from Fort Phil Kearny, an event historically referred to as the Fetterman Massacre.1

The engagement occurred when warriors under Chief High Backbone used a decoy tactic to lure the soldiers into a vulnerable position. The patrol’s commander, Captain William J. Fetterman, ignored warnings regarding this common strategy and pursued a decoy—who was the future military leader Crazy Horse—into an ambush. The entire group of approximately 80 U.S. soldiers was killed.1

At the time, this was the worst defeat suffered by the U.S. military on the Plains, and it served to reignite anti-Indigenous sentiment in the eastern United States. The conflict ultimately forced the U.S. government to abandon the Bozeman Trail and sign the Second Treaty of Fort Laramie in 1868, which guaranteed the Oceti Sakowin exclusive possession of their lands west of the Missouri River.12