The Oklahoma Land Rush of 1889 was the first land run into the Unassigned Lands of former Indian Territory, which had earlier been assigned to the Creek and Seminole peoples. The area that was opened to settlement included all or part of the Canadian, Cleveland, Kingfisher, Logan, Oklahoma, and Payne counties of the present-day US state of Oklahoma.

Sooners is the name given to settlers who entered the Unassigned Lands in what is now the state of Oklahoma before the official start of the Land Rush of 1889. The Unassigned Lands were a part of Indian Territory that, after a lobbying campaign, were to be opened to American settlement in 1889. President Benjamin Harrison officially proclaimed the Unassigned Lands open to settlement on April 22, 1889. As people lined up around the borders of the Oklahoma District, they waited for the official opening. It was not until noon that it officially was opened to settlement. The name derived from the "sooner clause" of Proclamation 288 — Opening to Settlement Certain Lands in the Indian Territory, which stated that anyone who entered and occupied the land prior to the opening time would be denied the right to claim land.