The Scientific Revolution began when astronomers questioned how the universe operates. By shattering long-held views, these astronomers opened a new world of discovery. The thinkers of the Enlightenment challenged old ideas about power and authority. Such new ways of thinking led to, among other things, the American Revolution. Between the 16th and 18th centuries, a series of revolutions helped to usher in the modern era in Western history. Revolutions in both thought and action forever changed European and American society.