DAKOTA TERRITORY. The Dakota Territory corresponded to the present states of North Dakota, South Dakota, and much of Wyoming and Montana. The first trading post in this region was built by Jean Baptiste Truteau in Charles Mix County, South Dakota, in 1794. The most famous trading post on the Missouri River was Fort Union, built at the mouth of the Yellowstone River in 1829. The Dakotas were mostly populated by the Sioux, or Dakota Indians, who resisted violently to protect their rights to the region after the discovery of gold in the Black Hills region of South Dakota led to an influx of white settlers and aggressive claims to the region by the United States government.
The United States reorganized its territorial claims to this region often. It all fell within the vast Missouri Territory created in 1812, part of which was added to Michigan Territory in 1834. In 1836, 1838, and 1849, Dakota became part of Wisconsin, Iowa, and Minnesota Territories, respectively. From 1834, the western part of the later Dakota Territory was designated Indian Country, and, in 1854, became part of Nebraska Territory. Dakota Territory, created by Congress in 1861, included lands west of present-day Minnesota and almost all of Nebraska Territory north of the forty-third parallel to the Missouri River. Montana Territory was cut off from Dakota Territory in 1864. When Wyoming Territory was created in 1868, Dakota Territory was reduced to the region comprising the two Dakotas of today, with a capital at Bismarck. In 1889, the territory was divided into the existing states of North Dakota and South Dakota.
Barbour, Barton H. Fort Union and the Upper Missouri Fur Trade. Norman: University of Oklahoma Press, 2001.
O. G.Libby/h. s.