Dakota Territory was the name of the northernmost part of the Louisiana Purchase of the United States. It became a historic, organized territory on March 2, 1861, and divided into the states of North Dakota and South Dakota on November 2, 1889. At times, the territory of Dakota Territory included parts of present-day Montana and Wyoming, the territory was reduced in 1863 to the present boundaries of the Dakotas.

The territorial capital was Yankton from 1861 until 1883, when it was moved to Bismarck. The admission of the two Dakotas, rather than one, was for a number of reasons. Firstly, the North and South of the territory had significant differences, not the least of which was the unabashed political corruption that had moved the territorial capitol from Yankton to Bismarck. On a national level, there was pressure from the Republican Party to admit the two states rather than one to add political power in the Senate.

See also

• Delegates to the United States House of Representatives from Dakota Territory
• Governors of Dakota Territory
• Historic regions of the United States