Who is this former leader of the Lakota nation?

Sitting Bull (c. 1831 – December 15, 1890) was a Hunkpapa Lakota holy man who led his people during years of resistance to 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.

Before the Battle of the Little Bighorn, Sitting Bull had a vision in which he saw many soldiers, "as thick as grasshoppers," falling upside down into the Lakota camp, which his people took as a foreshadowing of a major victory in which a large number of soldiers would be killed. About three weeks later, the confederated Lakota tribes with the Northern Cheyenne defeated the 7th Cavalry under Lt. Col. George Armstrong Custer on June 25, 1876, annihilating Custer's battalion and seeming to bear out Sitting Bull's prophetic vision. Sitting Bull's leadership inspired his people to a major victory. Months after their victory at the battle, Sitting Bull and his group left the United States for Canada, where he remained until 1881, at which time he and most of his band, returned to US territory, and surrendered to U.S. forces.