By March, 1770 a strong sense of resentment and general feelings of unrest among American colonists, who came mainly from Britain but were intermixed with many citizens from other European states, led to violent action against British regulations and troops. On the fifth of March in that year, British troops under the command of a nervy officer were ill-disciplined enough to open heavy musket fire against a mob of revolting citizenry in the major colonial city of Boston. The fusillade killed five Bostonians, and nine British soldiers were tried for murder in a hastily gathered tribunal. As the people of Boston predicted, the result of the trial was seven acquitted (including the nervous commander), and two soldiers convicted of manslaughter. It was not good enough, and led to further trouble.
The American Revolution (q.v.), happened because of colonists’ rage at attempts to impose direct taxation in the colonies without representation in London, in addition to a general increase of discontent with British rule within most of the thirteen colonies. In 1773, again in Boston, a ‘democratic’ group of working men mixed with larking students from colonial bourgeois families stripped off their clothes, dressed again as American natives, boarded ships in the harbour carrying (heavily taxed) tea sent from Emgland, and tipped nearly three hundred and fifty chests of the stuff into the harbour. There was little opposition. The harbour changed colour, and other North American ports disallowed entry to tea-carrying ships. With typical laconic American humour, this mild incident quickly became known as The Boston Tea Party. Recently, a new US political group has called itself ‘Tea-Party’ with an eye to history.
Parliament in London over-reacted to the Boston Tea Party, as might be expected: In 1774 the Members decided to punish naughty Massachusetts and Boston in particular. They passed the Boston Port Act, the Massachusetts Government Act, the Administration of Justice Act and something called a Quartering Act, which I assume had no connection with hanging, drawing and quartering. Later the angry English MPs added a Quebec Act for good measure. In fact the latter addressed a different problem, but colonists decided they were all intolerable so they lumped them together and named called The Intolerable Acts, by which name they are still remembered.
In July, 1776 the American colonists adopted their Declaration of Independence, but much bloodshed and mayhem followed and they had to wait until the Treaty of Paris in September, 1783 for the recognised and legal independence of the United States of America. The rest, as they say, is History.