Which 1787 law created a government for the Northwest Territory and banned slavery there?

The Northwest Ordinance created a government for the Northwest Territory and banned slavery there. Congress adopted it on July 13, 1787, under the Articles of Confederation, before the new Constitution was ratified.

The territory covered land north of the Ohio River and east of the Mississippi River. The ordinance established a path from territorial government to statehood: Congress could admit a territory as a state once its population and political institutions met specified conditions.

The law also protected religious liberty, encouraged public education, and recognized certain rights in the territory. Its slavery prohibition applied to the Northwest Territory, an area that later became all or parts of Ohio, Indiana, Illinois, Michigan, Wisconsin, and Minnesota. It is often confused with the Missouri Compromise of 1820, which addressed slavery's expansion in a different region and period.