Northwest Ordinance of 1787

Before the Constitution, an Early Federal Law Impacted Enslavement

Northwest Ordinance of 1787
Original Text of the Northwest Ordinance of 1787. Library of Congress

The Northwest Ordinance of 1787 was a very early federal law passed by Congress in the era of the Articles of Confederation. Its main purpose was to create a legal structure for the settlement of land in five present-day states: Ohio, Indiana, Illinois, Michigan, and Wisconsin. In addition, a major provision of the law prohibited enslavement north of the Ohio River.

Key Takeaways: Northwest Ordinance of 1787

  • Ratified by Congress July 13, 1787.
  • Prohibited enslavement in territories north of the Ohio River. It was the first federal law to address the issue.
  • Created a three-step process for new territories to become states, which established important precedents for the incorporation of new states through the 19th and 20th centuries.

Significance of the Northwest Ordinance

The Northwest Ordinance, ratified by Congress on July 13, 1787, was the first law to create a structure by which new territories could follow a three-step legal path to become a state equal to the original 13 states, and was the first substantial action by Congress to deal with the issue of enslavement.

In addition, the law contained a version of a Bill of Rights, which set out individual rights in the new territories. The Bill of Rights, which was later added to the U.S. Constitution, contained some of those same rights.

The Northwest Ordinance was written, debated, and passed in New York City during the same summer that the U.S. Constitution was being debated at a convention in Philadelphia. Decades later, Abraham Lincoln prominently cited the law in an important anti-enslavement speech in February 1860, which made him a credible presidential contender. As Lincoln noted, the law was proof that some of the nation's founders accepted that the federal government could play a role in regulating enslavement.

Necessity of the Northwest Ordinance

When the United States emerged as an independent nation, it immediately faced a crisis about how to handle the large tracts of lands to the west of the 13 states. This area, known as the Old Northwest, came into American possession at the end of the Revolutionary War.

Some states claimed ownership of western lands. Other states which asserted no such claim argued that the western land rightfully belonged to the federal government, and should be sold to private land developers.

States gave up their western claims, and a law passed by Congress, the Land Ordinance of 1785, established an orderly system of surveying and selling western lands. That system created orderly grids of "townships" designed to avoid the chaotic land grabs which had occurred in the territory of Kentucky. (That system of surveying is still evident today; airplane passengers can clearly see the orderly fields laid out in Midwestern states such as Indiana or Illinois.)

The problem with western lands was not entirely solved, however. Squatters who refused to wait for an orderly settlement began to enter western lands, and were chased off at times by federal troops. Wealthy land speculators, who wielded influence with Congress, sought a stronger law. Other factors, especially anti-enslavement sentiment in the northern states, also came into play.

Key Players

As Congress struggled to deal with the problem of land settlement, it was approached by Manasseh Cutler, a scholarly resident of Connecticut who had become a partner in a land company, the Ohio Company of Associates. Cutler suggested some of the provisions which became part of the Northwest Ordinance, in particular the prohibition of enslavement north of the Ohio River.

The official author of the Northwest Ordinance is generally considered to be Rufus King, a member of Congress from Massachusetts as well as a member of the Constitutional Convention in Philadelphia in the summer of 1787. An influential member of Congress from Virginia, Richard Henry Lee, agreed with the Northwest Ordinance because he felt it protected property rights (meaning it didn't interfere with enslavement in the South).

Path to Statehood

In practice, the Northwest Ordinance created a three-step process for a territory to become a state of the Union. The first step was that the president would appoint a governor, a secretary, and three judges to administer the territory.

In the second step, when the territory reached a population of 5,000 free White adult males, it could elect a legislature.

In the third step, when the territory reached a population of 60,000 free White residents, it could write a state constitution and, with congressional approval, it could become a state.

The provisions in the Northwest Ordinance created important precedents by which other territories would become states in the 19th and 20th centuries.

Lincoln's Invocation of the Northwest Ordinance

In February 1860, Abraham Lincoln, who was not widely known in the East, traveled to New York City and spoke at Cooper Union. In his speech he argued that the federal government had a role to play in regulating enslavement, and had, indeed, always played such a role.

Lincoln noted that of the 39 men who gathered to vote on the Constitution in the summer of 1787, four also served in Congress. Of those four, three voted in favor of the Northwest Ordinance, which, of course, contained the section prohibiting enslavement north of the Ohio River.

He further noted that in 1789, during the first Congress to assemble following the ratification of the Constitution, a law was passed to enforce the provisions of the ordinance, including the prohibition of enslavement in the territory. That law passed through Congress without objection and was signed into law by President George Washington.

Lincoln's reliance on the Northwest Ordinance was significant. At the time, there were fierce debates over enslavement splitting the nation. And pro-enslavement politicians often claimed that the federal government should have no role in regulating it. Yet Lincoln had deftly demonstrated that some of the same people who had written the Constitution, including even the nation's first president, clearly saw a role for the federal government in regulating the practice.


  • "Northwest Ordinance." Gale Encyclopedia of U.S. Economic History, edited by Thomas Carson and Mary Bonk, Gale, 1999. Research in Context.
  • Congress, U.S. "The Northwest Ordinance of 1787." The Constitution and Supreme Court, Primary Source Media, 1999. American Journey. Research in Context.
  • LEVY, LEONARD W. "Northwest Ordinance (1787)." Encyclopedia of the American Constitution, edited by Leonard W. Levy and Kenneth L. Karst, 2nd ed., vol. 4, Macmillan Reference USA, 2000, p. 1829. Gale Virtual Reference Library.
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McNamara, Robert. "Northwest Ordinance of 1787." ThoughtCo, Feb. 17, 2021, McNamara, Robert. (2021, February 17). Northwest Ordinance of 1787. Retrieved from McNamara, Robert. "Northwest Ordinance of 1787." ThoughtCo. (accessed June 4, 2023).