Amy Chua is a Yale University history professor who gave a speech in 2008 about the five Hyper Powers that have existed in history. The main thrust of her thesis is that societies that are open and tolerant of other people’s belief systems and customs were more successful than those that did not simply because they had access to more people and more ideas. More people could translate into more soldiers and more ideas into better ways of defeating one’s enemies. Click on this link to get to the lecture from iTunes – it is only 45min long and worth while listening to.
Rome stands out as one of her Hyper Powers, which then begs the question why did it collapse if it had both people and ideas in abundance? First, Rome was hit by several plagues in the 200s, 300s and then the Eastern Roman empire was hit by another big plague in the 500s. These plagues wiped out about a third of the population at a time. So Rome’s internal manpower reserves were actually relatively low. Germanic tribes, pushed west by other migrating peoples, fell into the Roman Empire in numbers that were simply too great for the Romans to absorb. Christianity, which had generally done well during times of plague in the 200s and 300s where care for the sick meant higher survival rates for believers, was hostile to non Christian beliefs. Society turned away from openness, became more stagnant and resulted in a loss of ideas.
To find out more you should listen to two complementary histories of Rome and Byzantium. Mike Duncan produced a wonderful 179 episode mega podcast of the History of Rome, ending at the fall of the Western Roman empire and Lars Brownworth produced a great 12 part episode on the History of Byzantium. Both are superb and highly recommended.