Delaware was the first state to ratify the U.S. Constitution, doing so on December 7, 1787.
The ratification occurred at a convention in Dover, where Delaware’s delegates approved the Constitution unanimously, 30–0. This early approval earned Delaware its enduring nickname, “The First State.”
Article Seven required approval from conventions in at least nine of the 13 states before the Constitution could take effect. Delaware’s action began the sequence of state ratifications; Pennsylvania followed five days later, and New Jersey ratified on December 18.
Delaware’s first-place status is sometimes confused with its position among the original colonies or with its ratification of the Articles of Confederation. The state joined the Confederation later than several other states, but it was first to approve the Constitution. New Hampshire became the crucial ninth state on June 21, 1788, while Rhode Island was the last of the original 13 to ratify.