Regarding a question such as this, it is worth noting that there were divisions among the colonists themselves (and a significant loyalist contingent wished to remain with Britain). Regardless, the American Revolution had its foundations in the long established traditions of colonial autonomy and self-governance, which dates back to the early history of American colonization.

With the end of the French and Indian War, however, Britain embarked on a policy change regarding the colonies—to bring them more closely in line with British economic interests. Thus, the British government began to impose acts of colonial taxation and to actively enforce British mercantile laws. The result was to inspire a backlash against these policies within the Colonies themselves (a backlash that would gradually intensify across the course of time).

Meanwhile, when reading the Declaration of Independence, you might well notice the influence of Enlightenment philosophy, particularly the work of John Locke and its concerns with tyrannical governance. There is a sense, in this document, that British policy in the pre-Revolutionary period was understood in terms of an abuse of power and an infringement upon colonial rights. Thus, the Revolutionaries argued that Britain had actively betrayed its own responsibilities where the colonies were concerned. Rather than being a legitimate government, the Revolutionaries perceived Britain as a hostile, tyrannical foe.

The colonists wanted to break away from Britain for many reasons.  They had enjoyed a great deal of autonomy before the French and Indian War due to the British policy of salutary neglect.  After the war, Parliament became more strict in demanding money.  The colonists wanted to keep the money and not give it to Parliament, in which they were not represented.  Parliament responded that members do not necessarily represent their district; rather, one member can speak for the good of the entire realm.  

The colonists also protested the Proclamation Line of 1763, which gave Native Americans land west of the Appalachians.  A considerable part of the colonial economy was made up of land speculation—the colonists needed this new land and resented being told that they could not have it.  Also, many colonists started to question whether this move was actually for their safety. Some suspected that it was designed in order to make them easier to tax on the coast.  

Finally, the colonists felt as though their rights had been abridged.  Colonial tax dodgers could be taken to Britain and placed in front of a panel of judges rather than being judged by a trial of their peers back in the colonies.  The Boston Massacre occurred when British soldiers fired upon a mob near a customs house.  The Tea Act made the colonists pay a tax on tea whether they actually used it or not.  As a result, some colonists dressed up as Indians and threw the tea into Boston Harbor.  Parliament then levied the Intolerable Acts. This led to the city of Boston being occupied as it would be if it was conquered enemy territory.  The colonists felt oppressed and felt as though Britain was not treating them as British citizens.  This is why they decided to obtain independence.  

Reasons as to why the colonists decided to break away from Britain can be found in the Declaration of Independence.

Deteriorating relations between the colonists and Britain was occasioned by Britain’s insistence on increasing taxes on its colonies, which also maintained their status within the empire.

The issue about taxes, among other laws, was compounded by the fact that the colonies were not represented in the British Parliament. The colonists argued that the British Parliament’s capacity should be restricted to serving Britain only and allow them to focus on their own legislatures.

The colonists sought intervention from the king on laws that were determined to be contrary to the constitution. However, the king sided with the British Parliament and issued a Proclamation of Rebellion, adding to the tension and resentment on the side of the colonists.

The king failed to give dialogue a chance and instead prepared to use violence in order to crush the mounting rebellion.

There were several reasons why the colonists wanted to break away from Great Britain. One reason is that the colonists believed that the British were violating their rights by requiring the colonists to pay the taxes created by the Stamp Act and the Townshend Acts. The colonists believed that they should have had representatives in Parliament that could speak about and vote on the proposed taxes. Since they didn’t have representatives in Parliament, they felt their rights were being violated.

Another cause is that the colonists believed that the British were trying to control them. When the British passed the Proclamation of 1763, the colonists believed the British were trying to prevent them from getting the land that the British had received from France as a result of the French and Indian War. When the British passed the Quartering Act, which required the colonists to provide housing for the troops enforcing this unpopular law, they were even more upset. The colonists were also unhappy with the Tea Act. This law gave the British East India Company a monopoly on the trade of tea.

When events turned violent in the 1770s, more colonists began to think they needed to be free from British rule. In the Boston Massacre, five colonists were killed when British soldiers fired into a crowd of protesters. After the Boston Tea Party, the British passed the Intolerable Acts. These laws punished the colonists, especially those in Massachusetts, for the Boston Tea Party. After fighting occurred at Lexington and at Concord in April 1775, it appeared only a matter of time before the colonists would declare their independence from Great Britain.