Einstein’s theories of relativity were the culmination of more than 2,000 years of human thought and scientific advancement, and they form the groundwork of how we believe the large-scale universe behaves. Yet, how exactly was Einstein able to conceive of a universe that operated on such peculiar principles as time dilation, length contraction, and the curvature of space and time? Beginning in the 4th-century BCE with Aristotle, this book aims to present a brief historical (non-mathematical) synopsis of the individuals and their ideas that influenced the development of the theories of relativity. It will examine the crucial scientific models that arose and how each contributed to Einstein’s envisioning special and general relativity. And as you will see, it was as much a philosophical journey as it was scientific.