Delaware was the first state to ratify the United States Constitution.
Delaware's ratifying convention approved the Constitution unanimously on December 7, 1787. The speed and unanimity earned Delaware the nickname “The First State,” a title that remains closely associated with its constitutional history.
The Constitution had been signed by delegates at the Philadelphia Convention on September 17, 1787, but it did not take effect immediately. Article VII required ratification by conventions in nine states. Delaware's approval was therefore the first step in the formal state-by-state process.
Pennsylvania was the second state to ratify, followed by New Jersey and Georgia. Virginia and New York joined later after intense debate. Rhode Island was the thirteenth and final original state to ratify, doing so in 1790, nearly two years after the Constitution became operative.