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In Dover, Delaware, the U.S. Constitution is unanimously ratified by all 30 delegates to the Delaware Constitutional Convention, making Delaware the first state of the modern United States.
Less than four months before, the Constitution was signed by 37 of the original 55 delegates to the Constitutional Convention meeting in Philadelphia. The Constitution was sent to the states for ratification, and, by the terms of the document, the Constitution would become binding once nine of the former 13 colonies had ratified the document. Delaware led the process, and on June 21, 1788, New Hampshire became the ninth state to ratify the Constitution, making federal democracy the law of the land. Government under the U.S. Constitution took effect on March 4, 1789.