In Western intellectual history, Isaac Newton has been attributed with the invention of absolute and universal time, empty and mathematical, which was later put into practice by increasingly more-sophisticated chronological and political technologies, leading up to the establishment of a global temporal standard in 1884. Already at the time of Newton, however, the invention of universal time was called into question by historians, philosophers and naturalists, who did not believe this was the answer to centuries of struggle with biblical, secular and natural chronologies. In this chapter, I will revisit this moment in the history of knowledge and explore the nature of the search for organizing principles in the field of historiography and in the genre of universal history. My focus will be on how seventeenth- and eighteenth-century universal history came into being by means of what I will refer to as the work of synchronization. In the seventeenth and eighteenth centuries, the one singular, homogenous, empty, linear and progressive time along which historiographers would arrange their narration, did not exist as such. Before historiographers could deploy this kind of universal, continuous temporality in their work, they had to make it, by activating synchronizing concepts, figures or practices in their works. Universal time was not made out of nothing, but by adapting and adjusting the different temporalities, temporal structures and orders, that is by synchronizing biblical times, chronological times, mathematical times, cosmological times, the times of different countries or nations, etc. Synchronizing all of these times into the one singular, homogenous time of universal history took a lot of work. This work and some of the tools involved in it constitute the topic of this chapter.