Han China, which began in 206 BCE, took shape as an empire in many of the similar ways that Imperial Rome, which began in a couple centuries later in 31 BCE, yet also differed in many aspects of empire building. Their rise to be is a major difference, while their supernatural sanction and absorption of foreign religion, as well as their collapse of empires, are two major similarities. While there were both similarities and differences in their imperial systems, they both were massive empires that, at the time, shaped the lives of close to half of the world's population. .
Rome's rise to be is thought of as an "unlikely rags-to-riches story. " It began, on the western side of central Italy, as a small, impoverished city-state. Eventually, Rome transformed into the center of an enormous imperial state that surrounded the Mediterranean basin, as well as parts of continental Europe, Britain, North Africa, and the Middle East. China, on the other hand, instead of creating something new like in Rome's case, their rise to be was a matter of restoring something old. After the fall of a Chinese state as one of the First Civilizations, the only thing that continued was an age of warring states, which consisted of endless rivalries with seven competing kingdoms. Qin Shihuangdi, a ruler that tried to unify China, succeeded in defeating the warring states and unifying China, developing an effective bureaucracy, adapting a philosophy called Legalism, and enjoying a rapidly rising agricultural output and a growing population. Within just a decade, China was reunified and the other warring states were defeated. While the Romans started from small and impoverished city-states, the Chinese began from a previous state. Both the Roman and Chinese started small and in shambles, but eventually became very large and successful empires. .
Supernatural sanction and the influence of foreign religious traditions, were both a factor in why the Roman and Chinese Empires were able to enjoy long periods of stability.