Why did the colonists declare independence from Britain?

The Declaration of Independence, based in part on the philosophy of John Locke, was an "expression of the American mind". Going back to Magna Carta, British nobles had petitioned the monarch demanding limits to his power. But Locke argues and the Declaration of Independence asserts that legitimate government is based on the consent of the governed. Locke's ideas were too democratic, too revolutionary for his time in England, but a century later they had a firm hold in the American colonies, and in 1776 they were the basis of the original and most fundamental American statement of rights, the Declaration of Independence.

America's Founders looked to the lessons of human nature and history to determine how best to structure a government that would promote liberty. They started with the principle of consent of the governed: the only legitimate government is one which the people themselves have authorized. But the Founders also guarded against the tendency of those in power to abuse their authority, and structured a government whose power is limited and divided in complex ways to prevent a concentration of power. They counted on citizens to live out virtues like justice, honesty, respect, humility, and responsibility.