September 17 in American History

September 17, 1787 — the Constitution is signed

After a summer of closed-door debate in Philadelphia, 39 delegates signed the U.S. Constitution — the framework that's governed the country ever since. It still needed ratification by nine states to take effect, but the document itself, argued line by line, was finished this day. Now celebrated as Constitution Day.

Founding DaySeptember 17 is also the anniversary of U.S. Constitution

Common Questions

What happened on September 17 in American history?

In 1787: the Constitution is signed. After a summer of closed-door debate in Philadelphia, 39 delegates signed the U.S.

Why is September 17 significant?

After a summer of closed-door debate in Philadelphia, 39 delegates signed the U.S. Constitution — the framework that's governed the country ever since. It still needed ratification by nine states to take effect, but the document itself, argued line by line, was finished this day. Now celebrated as Constitution Day.

Is September 17 an American holiday or anniversary?

September 17 is the anniversary of U.S. Constitution — Signed in Philadelphia — celebrated as Constitution Day. Founded 1787.

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