 Complete the following phrase:  During Harrisons administration, the Lakota Sioux, previously confined to reservations in South Dakota, grew restive under the influence of Wovoka, a medicine man, who encouraged them to participate in a spiritual movement called the Ghost Dance. Many in Washington did not understand the predomitly religious nature of the Ghost Dance, and thought it was a militant movement being used to rally Native Americans against the government. On December 29, 1890, troops from the Seventh Cavalry clashed with the Sioux at 