The U.S. Constitution was signed at Independence Hall on September 17, 1787, a founding milestone celebrated by America250.
The signing concluded the Constitutional Convention in Philadelphia after nearly four months of debate. Delegates had originally been authorized to revise the Articles of Confederation, but they produced an entirely new framework for a federal government with separate legislative, executive, and judicial branches.
Thirty-nine delegates signed the document, representing twelve states; Rhode Island had declined to send delegates. Signing did not itself put the Constitution into operation. It still required ratification by the states, and Article VII specified that approval by nine states would be sufficient for establishment among the ratifying states.