The Northwest Ordinance created the Northwest Territory of the United States in 1787.
The Confederation Congress enacted the measure on July 13, 1787. It organized lands north of the Ohio River, east of the Mississippi River, and south of the Great Lakes—an area that later contributed to several Midwestern states. The territory was the new nation’s first organized incorporated territory.
The ordinance established a process for territorial government and eventual statehood. It also prohibited slavery in the territory, although it did not end slavery elsewhere in the United States. The law encouraged the admission of new states on an equal footing rather than permanent colonial status.
Ohio became the first state formed from the Northwest Territory, entering the Union in 1803. Indiana, Illinois, Michigan, Wisconsin, and part of Minnesota also drew territory from it. The ordinance’s approach influenced later American territorial expansion.