The Confederation Congress enacted the Northwest Ordinance on July 13, 1787, to organize the territory northwest of the Ohio River.
Formally titled An Ordinance for the Government of the Territory of the United States, North-West of the River Ohio, the measure created the Northwest Territory. It established a territorial government, set rules for moving from territorial status toward statehood, and provided a framework for public land administration.
The ordinance became a major precedent for admitting new states rather than expanding the boundaries and political power of existing states. The territory eventually produced Ohio, Indiana, Illinois, Michigan, Wisconsin, and part of Minnesota. Ohio became the first state created from the Northwest Territory, entering the Union in 1803.
The ordinance also prohibited slavery in the territory while containing a fugitive-slave provision. The First Congress reaffirmed the measure, with modifications, in 1789. A frequent mix-up is identifying the Land Ordinance of 1785 as the law that created the territory; that earlier law mainly established a system for surveying and selling public land.