The Revolutionary War began in 1775 with the Battles of Lexington and Concord. George Washington was named Commander of the Continental Army. The Americans attacked Quebec in 1775 but failed to convince them to join the revolution. In 1776, the Continental Congress drafted and adopted the Declaration of Independence, declaring the colonies independent and justifying revolution based on natural rights. After France and Spain joined the Americans, the British surrendered at Yorktown in 1781 and formally recognized American independence in the 1783 Treaty of Paris.