The Revolutionary War began in 1775 between the United States and the British. The war was started as a bid for freedom by the U.S. from the rule of the British because of unfair taxing.
The colonies of America decided to break away as an independent country due to the unfair taxation pressed on them by the British. The war pitted the U.S. allied with France against the British. The war started out with protests, such as the Boston Tea Party, and ended in full-scale battles, like those in Lexington and Concord in Massachusetts. The American colonies set up a congress that wrote a letter to the king explaining their desire for independence, which was taken as an official declaration of war by the British.
Due to the British losses, support for the war quickly fell among the citizens of Great Britain, who quickly pushed for the end of the war. In 1783, the U.S. claimed victory and, after the signing of the Treaty of Paris, were finally recognized as an independent country. The U.S. ended up with more territory than originally intended while the British suffered great losses. France gained victory over the British as well, but suffered debt due to the cost of war.