Which 1787 law created the Northwest Territory and set rules for governing future U.S. territories?

The Northwest Ordinance created the Northwest Territory and established rules for governing future U.S. territories.

The Confederation Congress enacted the measure on July 13, 1787. It applied to land north and west of the Ohio River and east of the Mississippi River, an area acquired by the United States after the Revolutionary War.

The ordinance created a territorial government and described a path toward statehood. Once a territory reached a specified population, it could form a constitution and seek admission as a state. The system helped lead to the creation of Ohio, Indiana, Illinois, Michigan, and Wisconsin from the Northwest Territory.

The law also prohibited slavery in the territory and protected certain civil liberties, including religious freedom and trial by jury. Its provisions influenced later territorial legislation, although Indigenous nations living in the region were not treated as equal participants in the American expansion that followed.