Locke's political philosophy influenced the American Revolution the most. To demonstrate this, recall Thomas Jefferson's famous phrase from the Declaration of Independence: "Life, Liberty, and the pursuit of Happiness". This phrase actually appeared in the writings of Locke in his Two Treatises on Government where he says "no one ought to harm another in his life, health, liberty, or possessions." Jefferson changed the last condition from "possessions” because he feared people would claim they have the right to the property of others, so he claimed people have the right to pursue that which makes them happy. Locke also believed in the following political and philosophical principles, government is required to protect people's natural rights, government should have limited power, the type of government should be accepted by all citizens, absolute monarchy is immoral, government has an obligation to those it governs, and people have the right to overthrow government if the it fails its obligations or takes away natural rights (revolution).
Montesquieu wrote The Spirit of the Laws. His article described checks and balances on government by dividing the functions of power between three separate branches of government to protect liberty. One can see his ideas about separation of governmental powers reflected in the United States Constitution with the separate branches of government: the legislative, judiciary, and the executive.
Rousseau was the champion of democracy because he believed that authority lies with the people. In The Social Contract, written in 1762, Rousseau