Hunkpapa Lakota leader Sitting Bull is killed on Standing Rock Indian Reservation, leading to the Wounded Knee Massacre.

The Hunkpapa are a Native American group, one of the seven council fires of the Lakota tribe. The name Húŋkpapȟa is a Lakota word, meaning "Head of the Circle". By tradition, the Húŋkpapȟa set up their lodges at the entryway to the circle of the Great Council when the Sioux met in convocation. They speak Lakȟóta, one of the three dialects of the Sioux language.

The Lakota are a Native American people. Also known as the Teton Sioux, they are one of the three prominent subcultures of the Sioux people, with the Eastern Dakota (Santee) and Western Dakota. Their current lands are in North and South Dakota. They speak Lakȟótiyapi — the Lakota language, the westernmost of three closely related languages that belong to the Siouan language family.

Sitting Bull was a Hunkpapa Lakota leader who led his people during years of resistance against United States government policies. Sitting Bull was killed by Indian agency police accompanied by U.S. officers and supported by U.S. troops on the Standing Rock Indian Reservation during an attempt to arrest him at a time when authorities feared that he would join the Ghost Dance movement.

The Standing Rock Sioux Tribe of North & South Dakota controls the Standing Rock Reservation , which straddles the border between North and South Dakota in the United States, and is inhabited by ethnic "Hunkpapa and Sihasapa bands of Lakota Oyate and the Ihunktuwona and Pabaksa bands of the Dakota Oyate," as well as the Hunkpatina Dakota. The Ihanktonwana Dakota are the Upper Yanktonai, part of the collective of Wiciyena. The sixth-largest Native American reservation in land area in the US, Standing Rock includes all of Sioux County, North Dakota, and all of Corson County, South Dakota, plus slivers of northern Dewey and Ziebach counties in South Dakota, along their northern county lines at Highway 20.