Chief Joseph led his band of Nez Perce during the most tumultuous period in their history, when they were forcibly removed by the United States federal government from their ancestral lands in the Wallowa Valley of northeastern Oregon onto a significantly reduced reservation in the Idaho Territory. A series of violent encounters with white settlers in the spring of 1877 culminated in those Nez Perce who resisted removal, including Joseph's band and an allied band of the Palouse tribe, to flee the United States in an attempt to reach political asylum alongside the Lakota people, who had sought refuge in Canada under the leadership of Sitting Bull.