Northwest Ordinance

The Northwest Ordinance (formally An Ordinance for the Government of the Territory of the United States, North-West of the River Ohio, and also known as the Freedom Ordinance or "The Ordinance of 1787") was an act of the Congress of the Confederation of the United States, passed July 13, 1787. The primary effect of the ordinance was the creation of the Northwest Territory as the first organized territory of the United States out of the region south of the Great Lakes, north and west of the Ohio River, and east of the Mississippi River.

On August 7, 1789, President George Washington signed the Northwest Ordinance of 1789 into law after the newly created U.S. Congress reaffirmed the Ordinance with slight modifications under the Constitution. The Ordinance purported to be not merely legislation that could later be amended by Congress, but rather "the following articles shall be considered as Articles of compact between the original States and the people and states in the said territory, and forever remain unalterable, unless by common consent...."

Arguably the single most important piece of legislation passed by members of the earlier Continental Congresses other than the Declaration of Independence, it established the precedent by which the federal government would be sovereign and expand westward across North America with the admission of new states, rather than with the expansion of existing states and their established sovereignty under the Articles of Confederation. It is the most important legislation that Congress has passed with regard to American public domain lands. The U.S. Supreme Court recognized the authority of the Northwest Ordinance of 1789 within the applicable Northwest Territory as constitutional in Strader v. Graham, 51 U.S. 82, 96, 97 (1851), but did not extend the Ordinance to cover the respective states once they were admitted to the Union.

The prohibition of slavery in the territory had the practical effect of establishing the Ohio River as the boundary between free and slave territory in the region between the Appalachian Mountains and the Mississippi River. This division helped set the stage for national competition over admitting free and slave states, the basis of a critical question in American politics in the 19th century until the Civil War.