Thirty-nine delegates signed the United States Constitution, the later founding document linked to America250.
The signing took place on September 17, 1787, at Independence Hall in Philadelphia, the same building where Congress adopted the Declaration of Independence eleven years earlier. The delegates had spent about four months debating and drafting a new framework for government.
The Constitutional Convention began with delegates from twelve states; Rhode Island declined to send delegates. Although 55 delegates attended at various points, 39 endorsed the final document. Some delegates had already left, and three of those present refused to sign.
The Constitution was then submitted to the states for ratification. Article VII required approval by nine states for it to take effect, creating a process different from the unanimous ratification once required under the Articles of Confederation.