What is the time period known as the Age of Enlightenment?

Most consider the Age of Enlightenment to have ended with the start of the French Revolution in 1789. For more than a century before that the discoveries of scientists, such as Galileo, and ideas of philosophers, such as Rene Descartes, had led people into a rejection of the automatic respect for kings and the Christian priesthood that had been common in Europe during and since the Middle Ages. All nations contributed to the Enlightenment agenda, but the French led the way during the 18th century. The writings of Denis Diderot, Voltaire and D'Alembert, all French, provided the material for the supporters of the Enlightenment to take the argument to the traditionalists. These writers lived in the reign of King Louis the Fifteenth of France (1715-1774).