How did the Northwest Ordinance established procedures for the orderly expansion of the United States?

Question

This happened somewhere between the timeline of 1865 and 1896...

Answer 1

I think you mean 1787.

Many consider this to document to be second only to the Declaration of Independence in importance.  It first appeared in a supplement to the First Volume of the Columbian Magazine in Philadelphia, and was passed unanimously by the Congress of the Confederation on July 13, 1787.

It served as a kind of “Letter of Intent” that this land would in fact be settled and would become a part of the United States, and it set the precedent that the United States would expand by adding new states, rather than to expand existing states.

Based on lines originally laid out by Thomas Jefferson in 1784, this area north of the Ohio River and west of the Mississippi River became what are now the states of Illinois, Indiana, Michigan, Ohio, and Wisconsin.

This area had been obtained by Great Britain, and closed to white settlement by the Proclamation of 1763.  At the end of the Revolutionary War, the United States claimed the land, but it was disputed by the states of Connecticut, Massachusetts, New York, and Virginia.

It was Jefferson who proposed that these states yield their claims to the territory and that it be divided up into newly created states.

More than just accelerating westward expansion, the Northwest Ordinance also spelled out provisions for the advancement of education, civil liberties, and the exclusion of slavery.