Final answer:
The Enlightenment was an 18th century philosophical movement that emphasized reason and influenced the Founding Fathers in shaping the American Revolution.
Step-by-step explanation:
The Enlightenment was a philosophical movement in 18th century Europe that emphasized the use of reason and advocated ideals such as liberty, progress, and separation of church and state. It was important to US history as the ideas and ideals of the Enlightenment influenced the Founding Fathers and shaped the American Revolution. For example, thinkers like John Locke, Montesquieu, and Rousseau inspired concepts of individual rights, the balance of power among branches of government, and the social contract.