The first document that established the government of the United States was the Articles of Confederation. It was drafted by the Second Continental Congress between July 1776 and November 1777 and came into force on March 1, 1781, after ratification by all 13 states. The Articles served as the nation's first frame of government during the American Revolution and created a confederal government that preserved the independence and sovereignty of the states while providing a framework for a league of friendship among them.

Later, the U.S. Constitution, signed on September 17, 1787, replaced the Articles of Confederation and established the federal government structure still in use today. But the Articles of Confederation were the first formal agreement to establish the United States government.