The Age of Reason, also known as the Age of Enlightenment cased a radical shift in the dynamics of political power and governance between the government and the governed. It did so by denying the monarchic postulate of the so-called divine right of royalty and nobility to rule over the majority; and by asserting the doctrines of social contract, of natural rights and of popular sovereignty.
American colonists, based on such principles, abolished monarchy and all other ties with the Kingdom of Great Britain and instituted a democratic form of government based on popular vote, elections and term limits for their rulers as well as the system of checks and balances and separation of powers in order to prevent tyranny.
Not a long time later, the French revolutionaries would do the same by deposing King Louis XVI of France and abolishing monarchy.
America has the merit of eliminating British Royal rule over its territory. France as the merit of eliminating the King himself and all monarchy.