This work brings together studies of a wide variety of millenarians who were active in the 17th and 18th centuries in France, The Netherlands, Germany, Sweden, and eastern Europe. The sheer variety of millenarian ideas and movements and their myriad of ebbs and flows and interactions teach us that millenarianism was a much more complex and influential factor than most studies have recognized. It was part and parcel of the growth of science, the progress of philosophy, and the genesis of political reform.