What Day Was the signing of the US Constitution?

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Delegates to the Constitutional Convention in Philadelphia signed the finished US Constitution, concluding roughly four months of closed-door debate over how to replace the weaker Articles of Confederation with a stronger federal framework.

Thirty-nine of the 55 delegates who had attended signed the document; several others, including prominent figures like George Mason, declined to sign over concerns about the lack of a bill of rights.

The Constitution didn't take legal effect immediately — it required ratification by nine of the thirteen states, a process that took nearly another year to complete.

Benjamin Franklin, then 81 and the convention's oldest delegate, reportedly had to be carried to the signing in a sedan chair due to his poor health, yet still added his support to the final document.