In what ways were the Roman empire and the Han empire similar and in what ways were they different?
The Han dynasty in China maintained a remarkable level of similarity with its predecessor dynasty, the Qin, founded by the first emperor Qin Shi Huangdi. The Han dynasty borrowed many traditions from the Qin, such as the creation of a highly centralized state, a systematic bureaucracy, a large military, and a unified system of writing. With these very effective tools of statecraft, Han emperors claimed to rule “Under All Heaven”—Tianxia—which to them was literally all of the known world. This idea fell under the general rubric of the Han ideology known as the “Mandate of Heven,” by which each successive Han emperor claimed that heaven had given them the right to rule all of Tianxia, the previous emperor having lost that right.
In many important ways, the Roman empire demonstrated similarity to this style of rulership. With the advent of Octavian to a position of unprecedented power in the Senate, the republican period ended, and the Roman empire was officially born in 27 BCE. Octavian, and all of the emperors that came after him, claimed to rule through imperium, which literally means “command” but was usually applied in military sense. This bore similarity to (but was not the exact same thing as) the concept of the Han dynasty's Mandate of Heaven. Some Roman philosophies also bore strong resemblance to Chinese ways of thinking during the same period. Hellenistic Stoic philosophers such as Epictetus, for example, claimed that the entire Mediterranean basin was one large “ecumene” because all of its inhabitants shared a common Greek language and way of thinking. In this way, the Stoic (and other) philosophies that allowed Romans to mentally unify their empire were similar to Han conceptions of Tianxia that served similar functions.
One critical way in which these empires were different was their conceptualization of power. The Roman empire had been built on the principles of res publica—the “public thing.” The idea of res publica implied that even when the emperors held the most dictatorial powers in the Senate, this institution was still a representation of the collective demands of the citizens of the empire. In practice, of course, most ordinary Roman citizens were powerless. But this very idea conflicted with the Han understanding of the Mandate of Heaven, which was by its very nature a private blessing. The Mandate that was bestowed on a Han emperor came from the sky, and it was a reward for virtuous and ethical behavior. Though anyone could theoretically gain heaven’s favor, once an individual did obtain the Mandate and began his rule, it was his alone.