The British allowed Britain's East India Company to sell Indian tea to America without taxes. It irritated local interest groups such as the Sons of Liberty, so, they staged the Boston Tea Party incident.
In December 1773, they boarded a British ship and threw chests of tea into Boston Harbor. This angered the British and led to physical conflicts. The East India Company also sold opium to China, leading to the First Opium War (1839-1842) and marked the first step of Britain's rule over Hong Kong until 1997.
To punish the American colonists, the British Parliament passed the Intolerable Acts, which limited the size of the colonists' government. The colonists rejected these laws and called them the Coercive Acts to express their anger towards Britain.
In October 1774, the representatives of the thirteen colonies held the First Continental Congress in Philadelphia to discuss how to handle Britain. They submitted a petition to King George III of Britain requesting him to remove the Intolerable Acts.
On April 19, 1775, the physical clash between Britain and the American colonists at Lexington, marked the beginning of the American Revolutionary War. This event is seen as the ‘birthplace of American liberty.’
On July 4, 1776, the Second Continental Congress took place in Philadelphia. The Declaration of Independence was signed. It explained why the thirteen colonies regarded themselves as independent states, and no longer subject to British colonial. 4th July is now celebrated as the national day of the United States.