At the time of Jesus' birth, thousands of people were leaving their families and tribes behind and flocking into brand new multi-ethnic cities. The world was undergoing the first phase of globalization, and in this ferment rulers and ruled turned to religion as a source of order and stability. The world was full of gods, competing and merging with one another. Selina O'Grady takes the reader on a journey across the empires of the ancient world and introduces us to rulers, merchants, messiahs, priests and holy men. Throughout, she seeks to answer why, amongst the countless options available, the empires at the time "chose" the religions they did? Why did China's rulers hitch their fate to Confucianism, a philosophy more than a religion? And why was a tiny Jewish cult eventually adopted by Rome's emperors rather than the far more popular and widespread cult of Isis? O'Grady looks at why and how religions have had such an immense impact on human history and in doing so uncovers the ineradicable connection between politics and religion--a connection which still defines us in our own age.