Ancient Rome has always been a symbol of secular power, but you can't understand the might of this city without also grasping the sacred beliefs of the Romans themselves. Right through its history, Rome's greatness was inextricably linked to its sacred mission. For its first thousand years, Rome's palaces and temples expressed one thing - this was a holy city, blessed by the gods to rule the world. But all that was to change. A new god was about to take Rome. Next time, Rome's transformation from pagan heartland to the capital of Christendom, as religious revolution hits the Holy City.