Who was the first delegate to sign the United States Constitution?

George Washington was the first delegate to sign the United States Constitution.

Washington signed on September 17, 1787, as president of the Constitutional Convention. The convention's delegates then signed by state, following the order of the states from north to south. Washington's prominent position near the document's right margin reflects his role in presiding over the proceedings.

Washington was not the Constitution's principal writer. James Madison played a major role in preparing the Virginia Plan and is often called the “Father of the Constitution,” while Gouverneur Morris drafted much of the final wording. Benjamin Franklin also signed and delivered a notable closing appeal for unity.

The signing did not itself establish the Constitution as the nation's operating law. Ratification by state conventions was still required under Article VII. New Hampshire became the ninth state to ratify in June 1788, and the federal government began operating under the Constitution in March 1789.