The American Revolutionary War fought by the Thirteen Colonies against the British Empire was the first successful war of independence by a non-European entity against a European power in modern history. Americans had developed an ideology of "republicanism", asserting that government rested on the will of the people as expressed in their local legislatures. They demanded their "rights as Englishmen" and "no taxation without representation". The British insisted on administering the empire through Parliament, and the conflict escalated into war.[78]
In 1774 the First Continental Congress passed the Continental Association, which mandated a colony-wide boycott of British goods. The Second Continental Congress, an assembly representing the United Colonies, unanimously adopted the Declaration of Independence on July 4, 1776 (annually celebrated as Independence Day).[79] In 1781, the Articles of Confederation and Perpetual Union established a decentralized government that operated until 1789.[79]
After its defeat at the Siege of Yorktown in 1781, Britain signed a peace treaty. American sovereignty became internationally recognized, and the country was granted all lands east of the Mississippi River. Tensions with Britain remained, however, leading to the War of 1812, which was fought to a draw.[80] Nationalists led the Philadelphia Convention of 1787 in writing the United States Constitution, ratified in state conventions in 1788. Going into force in 1789, this constitution reorganized the federal government into three branches, on the principle of creating salutary checks and balances. George Washington, who had led the Continental Army to victory, was the first president elected under the new constitution. The Bill of Rights, forbidding federal restriction of personal freedoms and guaranteeing a range of legal protections, was adopted in 1791.[81]