The Northwest Ordinance of 1787 established a framework for the governance and settlement of the Northwest Territory, the region north of the Ohio River. It created a system for admitting new states to the Union on an equal footing with the original thirteen, prohibited slavery in the territory, and guaranteed civil liberties. The ordinance was a landmark achievement of the Articles of Confederation government and set a precedent for westward expansion. It is considered one of the most important pieces of legislation in American history.

The Northwest Ordinance is a foundational document in the literature of American expansion, embodying the ideals of freedom and equal representation. Its prohibition of slavery has been a subject of historical poetry and prose, celebrating it as a step toward a more just society. The ordinance is often referenced in works that explore the themes of Manifest Destiny and the nation's expansion across the continent.