Answer:
The main reason the colonies started rebelling against 'mother England' was the taxation issue. The colonies debated England's legal power to tax them and, furthermore, did not wish to be taxed without representation. This was one of the main causes of the Revolutionary War.
Explanation:
British Strengths and American Weaknesses
The British seemed unbeatable. During the previous 100 years, the British had enjoyed triumph after triumph over nations as powerful as France and Spain. At first glance, the odds were clearly against the Americans. A closer look provides insight into how the underdogs emerged victorious.

Britain's military was the best in the world. Their soldiers were well equipped, well disciplined, well paid, and well fed. The British navy dominated the seas. Funds were much more easily raised by the Empire than by the Continental Congress.
Some of those funds were used to hire Hessian mercenaries to fight the Americans.
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Disease is what i would guess their medical stuff wasn't very great so most of them died from various diseases
