In February 1778, France formally recognized the United States and concluded a military alliance. To prevent a Franco-American alliance, Britain repealed the Coercive Acts and the Tea Act and sent peace emissaries to Philadelphia. However, the United States had already ratified the treaty with France. In June 1778, France declared war on Britain; in June 1779, Spain allied with France and joined the anti-British war; by December 1780, the Netherlands also declared war on Britain. Britain found itself internationally isolated.

With assistance from France and others, the American forces began a counteroffensive in 1781, moving south to campaign in South Carolina and forcing the British to retreat to the coast. In August 1781, the British held their positions in Yorktown, Virginia. The combined French and American forces, under Washington’s command, totaling 17,000 troops, completed the encirclement of Yorktown. With no escape route, the British had no choice but to negotiate surrender. On October 19, 1781, 8,000 British troops stationed at Yorktown formally surrendered. Thereafter, only sporadic skirmishes occurred, and major fighting had effectively ceased.

After the Siege of Yorktown, the British Parliament was forced to approve peace negotiations. On November 30, 1782, Britain and the United States signed the draft of the Treaty of Paris; on September 3, 1783, the United States became an independent nation, comprising the thirteen states, with boundaries extending north to the Great Lakes, west to the Mississippi River, and south to the 31st parallel.

During the eight-year Revolutionary War, the American side included 44,000 militia, 35,000 Continental Army soldiers, 15,000 French troops, and 8,000 Spanish troops. The British side included 30,000 British regulars, 40,000 German troops, 50,000 foreign mercenaries, and 5,000 Native Americans.

On the American side, 25,000 were killed and 25,000 wounded. On the British side, 24,000 were killed and 20,000 wounded.

Looking at the Anglo-American war overall, a total of 50,000 deaths over eight years is relatively low. This is partly due to the limited destructive power of contemporary weapons and the small population of the colonies at the time, but it also reflects the Western value placed on preserving life. In Anglo-American warfare, the rule was simple: fight if you can win, retreat if you cannot, and surrender if there is no escape. Those who surrendered could return home and were still accepted by their communities. During the eight-year conflict, both sides had several occasions in which thousands were captured or surrendered, unlike the Japanese, who followed the emperor to the death and refused to surrender.