Yankton, South Dakota Yankton, South Dakota Yankton is a city in, and the county seat of, Yankton County, South Dakota, United States. The population was 14,454 at the 2010 census. Yankton is the principal city of the Yankton Micropolitan Statistical Area, which includes the entirety of Yankton County, and which had an estimated population of 22,662 as of July 1, 2017. Yankton was the first capital of Dakota Territory. It is named for the Yankton tribe of Nakota (Sioux) Native Americans; Yankton is derived from the Nakota word "I-hank-ton-wan" ("the end village"). Yankton is located on the Missouri River just downstream of the
Leschi (Native American leader) Leschi (Native American leader) Chief Leschi (; 1808 – February 19, 1858) was chief of the Nisqually Native American tribe. He was hanged for murder in 1858, but exonerated in 2004. Leschi was born in 1808 near what is today Eatonville, Washington, to a Nisqually chief and a Klickitat woman. He was appointed chief by Isaac Stevens, first governor of Washington Territory, to represent the Nisqually and Puyallup tribes at the Medicine Creek Treaty council of December 26, 1854, which ceded to the United States all or part of present-day King, Pierce, Lewis, Grays Harbor, Mason, and Thurston Counties and