Curtis S. answered 03/14/19
American History Specialist, Writer, and Tutor
Sorry that you're overloaded! The answer to your question is by no means short nor uncomplicated. It begins with the French and Indian War where England wanted the colonies to bear their fair share of the costs of defending the American frontier. That led to taxation and American resistance to measures like the Stamp Act and the Townsend taxes. Things got serious up in Boston with the Boston Tea Party, the Boston Massacre and open rebellion and the early years of the rebellion.
The short answer to your question is "British Taxation" and King George's refusal to listen to the colonists' complaints. The chronology of events begins in 1760 and ends with American Independence.
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