Sitting Bull (Lakota: Tȟatȟáŋka Íyotake [tˣaˈtˣə̃ka ˈi.jɔtakɛ] ;[4] c. 1831 – December 15, 1890) was a Hunkpapa Lakota leader who led his people during years of resistance against United States government policies. He was killed by Indian agency police 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.