Article Seven required nine state ratifications to establish the United States Constitution.
The Constitution’s framers set the threshold at nine of the thirteen states. This meant the new framework could take effect without waiting for unanimous approval from every state, although the political future of the remaining states still mattered greatly.
New Hampshire supplied the decisive ninth ratification on June 21, 1788. The Constitution therefore reached its Article Seven threshold before North Carolina and Rhode Island had ratified. North Carolina joined in 1789, while Rhode Island became the final original state to ratify in 1790.
The requirement applied to state conventions rather than direct nationwide voting. Article Seven also specified that ratification documents would be deposited with the Confederation Congress. The rule is distinct from later constitutional amendment procedures, which require approval by three-fourths of the states.