The United States' first constitution was the Articles of Confederation. It was adopted by the Continental Congress on November 15, 1777, and served as the nation's first frame of government. The Articles established a confederation of sovereign states with a weak central government, and it was officially in force from March 1, 1781, until 1789 when the current U.S. Constitution took effect. The Articles created a "league of friendship" among the 13 states, with each state retaining most powers except those explicitly delegated to the national government. Representation in Congress was equal for each state, regardless of population.