The Enlightenment had a profound impact on modern political institutions by advocating for reason, individual rights, and the idea of government by consent. Enlightenment thinkers like Locke, Rousseau, and Montesquieu criticized absolute monarchy and promoted democratic ideals, such as separation of powers and checks and balances. These concepts influenced constitutions around the world, particularly the United States Constitution and the French Declaration of the Rights of Man and of the Citizen. Enlightenment principles laid the foundation for modern democracies, emphasizing liberty, equality, and justice, prompting movements advocating for civil rights and alterations in governance that aimed to better reflect the will of the people.