Whereas Plato anticipated Marx in giving a rational analysis of the class system, Aristotle indulged in such hollow abstractions as the Many, the Few, the One, the Good, the Bad. If the Many rule themselves well, this is Polity. If they rule badly, not taking into account the needs of the rich, it is Democracy. If the Few rule society well, they are an Aristocracy. If they rule society badly & selfishly they are an Oligarchy. If One man rules well, he is a King. If he rules badly, he is a Tyrant. Aristotle anticipated the U.S. notion of the virtue, not of the middle class as defined by Plato & Marx (the merchants), but of those of middle income, as a stabilizing force in society, based upon the highly questionable notion of some relation between a median income & the philosophical moderation of the Golden Mean. Aristotle said that, in Good government, the rule of the Few is better than of the Many, but the rule of One is best. The cosmos is a unity. Unity is Good. Unity is Aristotle's central principle when speaking of art. (I don't argue with that; it's a general classical idea.) In government, the government of one is most unified, & therefore best. with Bad governments it is the opposite. The Bad Few are worse than the Bad Many, & the Bad One is worst of all, the Tyrant being a unity in pursuit of the Bad.
Philip of Macedonia conquered Greece, & made Aristotle the teacher of his son Alexander. Alexander took Aristotle too seriously, & decided to become the Good King of the world, & make it a political unity. He got as far as India, bringing Greek culture wherever he conquered. In Egypt he founded Alexandria, which became a center of Egypto-Greek culture until the fall of Rome. The cosmos did not favor a Universal Monarchy at that time however, & struck Alexander down in his early 30's with some kind of disease. Alexander's empire was too big for a lesser man, & was divided into three parts by his generals, becoming three separate kingdoms, centered in Greece, Syria, & Egypt, & referred to in the book of Daniel as the Kingdoms of the West, North, & South respectively. Cleopatra was of the Greek dynasty of Egypt. In India, within a decade of Alexander's death, Candragupta revolted against Greek rule there, & founded the Maurya dynasty, which produced great Greek influenced Indian art. Candragupta's grandson Asoka caught the Aristotelian bug & decided to become a Universal Monarch, conquering most of India. Then he converted to Buddhism & repented. Aristotle's Good was the Buddha's Bad.
Rome began as a kingdom, but became a republic, & later an empire. Like the Greeks, the Romans were a warrior society. But they claimed to fight only defensive wars. Their expansion, they said, was always for the sake of their own security; they conquered unruly neighbors because they had no choice. This was not always true. But they pointed to the Roman Peace as a proof that it was generally true. They had a policy of fighting small wars to avoid large ones, the opposite of the 20th century policy of crying out against small just wars in favor of peace, in order to create enough international tension for a world war. Similar is the outrage against chemical warfare in Iraq, in order that we may have a nuclear war in South Asia. Or somewhere. When Rome conquered the Greek remnant of Alexander's empire, the Romans absorbed Greek culture, & spread it wherever they went. They set up a vast & efficient civil service which continued to operate efficiently even under the maddest emperors. Their laws, though different for Roman citizens, subject populations, & slaves, were uniform & relatively rational & just considering the class distinctions of that time. There was no hypocrisy in the class system, at least, & no racism in slavery. Modern law continues to be influenced by Roman law. Meanwhile the law of Moses continues to create such cases as that of Ms Lewinsky.
Caligula extended Roman citizenship to the whole empire.