During the Revolutionary War, the 13 American colonies fought against Britain. The colonists rebelled because they felt they were being taxed unfairly by the British Parliament, and Britain was imposing increasingly punitive laws against them.
Fighting first broke out between the colonists and the British at the Battle of Lexington and Concord in April 1775. In July 1776, the colonies formally declared their freedom from British rule with the signing of the Declaration of Independence. The colonies then became the 13 states that would form the United States of America. A peace treaty signed in 1783 signaled the official end of the war.
The major financiers of the revolutionaries were France, the Dutch republic and Spain. It is because of their involvement that Britain eventually declared war on the three countries.