Rhode Island was the last of the original thirteen states to ratify the United States Constitution.
Its ratifying convention approved the Constitution on May 29, 1790, nearly three years after the document had been signed. Rhode Island had initially rejected the Constitution in a statewide referendum in 1788 and did not send delegates to the Constitutional Convention in Philadelphia.
The Constitution had already taken effect after New Hampshire became the ninth state to ratify it on June 21, 1788. Rhode Island's later approval was still politically important because it completed participation by all thirteen original states.
North Carolina was also late, ratifying in November 1789, but it was not last. Rhode Island's opposition reflected concerns about federal power, individual rights, and the absence of a bill of rights. The later adoption of the Bill of Rights in 1791 addressed some of those concerns, although Rhode Island's ratification itself came before those amendments were approved.