Stillwater was founded after a Land Run in 1889.
The Springer Amendment was immediately added to the Indian Appropriation Act of 1889 to authorize settlement under the provisions of the Homestead Act of 1862. The amendment, however, denied the settlers their squatter's rights. The lands were to be settled by a land run. The original settlers were rounded up and expelled. On April 22, 1889, the Oklahoma lands were settled by what would later be called the Run of '89. Over 50,000 people entered on the first day, among them several thousand former slaves and descendants of slaves.
Tent cities grew overnight at Oklahoma City, Kingfisher, El Reno, Norman, Guthrie and Stillwater, which was the first of the settlements.
Federal troops provided law enforcement and the closest criminal and civil jurisdictions were the federal courts in Fort Smith, Arkansas. Despite that, the district was generally peaceful. Most land disputes were settled without bloodshed, although a few took years to resolve.
The Organic Act of 1890 incorporated the Unassigned Lands into the new Oklahoma Territory. Under the act local officials were appointed to handle civil and criminal matters until elections were held. In 1907 Oklahoma became the 46th state.
Source
Wikipedia.