Delaware was the first U.S. state to ratify the Constitution, doing so on December 7, 1787.
The ratification took place at a convention in Dover, Delaware. Delegates approved the Constitution unanimously, with a vote of 30–0. This made Delaware the first of the 13 states to accept the new national framework.
Article VII of the proposed Constitution required approval from nine states for it to take effect. New Hampshire became the ninth state to ratify it on June 21, 1788, while Rhode Island was the last of the original 13 states, ratifying it on May 29, 1790.
Delaware’s early ratification earned it the nickname “The First State.” This title refers specifically to its position in the Constitution’s ratification sequence, not to being the first colony founded or the first place to declare independence. Delaware was also among the 13 colonies that became the United States during the American Revolution.