The Territory of Dakota was an organized incorporated territory of the United States that existed from March 2, 1861, until November 2, 1889, when the final extent of the reduced territory was split and admitted to the Union

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 as the states of North

North Dakota

North Dakota is a state located in the Midwestern region of the United States of America, along the Canadian border. The state is bordered by Canada to the north, Minnesota to the east, South Dakota to the south and Montana to the west. North Dakota is the 19th-largest state by area in the U.S....

 and South Dakota

South Dakota

South Dakota is a state located in the Midwestern region of the United States. It is named after the Lakota and Dakota Sioux American Indian tribes. Once a part of Dakota Territory, South Dakota became a state on November 2, 1889. The state has an area of and an estimated population of just over...

.

The Dakota Territory consisted of the northernmost part of the land acquired in the Louisiana Purchase

Louisiana Purchase

The Louisiana Purchase was the acquisition by the United States of America of of France's claim to the territory of Louisiana in 1803. The U.S...

 of the United States. The name refers to the Dakota branch of the Sioux

Sioux

The Sioux are Native American and First Nations people in North America. The term can refer to any ethnic group within the Great Sioux Nation or any of the nation's many language dialects...

 tribes which occupied the area at the time.