“Voltaire” is the pen name under which French author-philosopher François-Marie Arouet published a number of books and pamphlets in the 18th century. He was a key figure in the European intellectual movement known as the Enlightenment. Voltaire was quite controversial in his day, in no small part because of the critical nature of his work. His books and pamphlets contained scores of assaults on church authority and clerical power. They criticized French political institutions too, and many incorporated elaborate defenses of civil liberty. Voltaire’s ideas ultimately found expression in the French and American revolutions.