Video: 'On This Day: June 21, 1788'

(Saturday, June 21, 1788) — The United States Constitution, the supreme law of the United States of America featuring a stronger federal government under a system of checks and balances known as the separation of powers doctrine, went into effect today as New Hampshire (by a vote of 57-47) became the ninth and last necessary state of the original 13 colonies to ratify it.

The revised federal structure, which would replace the Articles of Confederation, would become effective on March 4, 1789.

Video: 'The Making of the Constitution.'