Delegates signed the United States Constitution on September 17, 1787, a landmark event connected with America250.
The signing occurred at the Pennsylvania State House, now Independence Hall, in Philadelphia. It concluded the Constitutional Convention, which had met for nearly four months to design a stronger federal government.
Thirty-nine delegates endorsed the document. George Washington, the convention’s presiding officer, signed first, followed by delegates grouped by state. Several delegates, including Benjamin Franklin, supported the final compromise even though the convention had produced disagreements over representation and executive power.
September 17 is Constitution Day in the United States. The signing did not immediately make the Constitution operative: it still required ratification by the states. New Hampshire became the ninth ratifying state on June 21, 1788, and the new federal government began operating under the Constitution on March 4, 1789.