The U.S. Constitution was drafted during the notoriously hot summer of 1787 and signed by delegates to the Constitutional Convention in Philadelphia on September 17 of that year. Delaware was the first state to approve it, in December, and it went into effect on June 21, 1788, when New Hampshire became the ninth state to ratify, the threshold required to make the new governing document legally binding.
HISTORY’s Moment in Media: The Bill of Rights Clears Congress
