Why Ancient Rome Needed Immigrants to Become Powerful

The Caesars embraced newcomers, less out of idealism than out of self-interest.
By Barry Strauss

How “Roman” was the Roman Empire? Well, by some measures: not very.

As the Roman emperors sought to expand and strengthen their empire, they recognized that immigration was a means for both. Although the Roman elites sneered at immigrants, the emperors welcomed them into the labor force and military, keenly understanding that for the empire to grow and thrive it had to have new blood. Not only was the populace changing but the emperors themselves came from diverse backgrounds, from Spain to Syria.

Their legions contained ever fewer Italians, let alone Romans. Rome became a melting pot, in many ways as much a Greek city as a Latin one, and with African, Celtic, Egyptian, German and Jewish populations as well. But not everyone was pleased with the emperors' approach to immigration.

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Writing in the late first century AD, for example, the poet Juvenal invents a character who can’t bear how Greek the city of Rome had become, what with its Greek-speaking population and their customs. He complains in frustration, “For a long time now the Syrian River Orontes has flowed down into the Tiber.” For that matter, some Greeks were equally xenophobic, like the Greek satirist Lucian (second century AD), who scorned coarse Roman patrons. But snobbery could not stem the tide of change.

An ancient Roman military parade. Immigrants comprised much of the Roman army. 

Hulton Archive/Getty Images

Between roughly 300 BC and AD 200, millions of immigrants came to Italy. Most arrived in chains, as slaves, the victims of Rome’s wars of expansion or of piracy. But others came of their own free will, either to seek their fortune or to lose themselves in the anonymity of a big city; with a population of about a million, Rome was the largest city in Europe or the Mediterranean. In this cosmopolitan place, people of various backgrounds and skill sets saw opportunities abounding.

The emperors embraced the newcomers, less out of idealism than out of self-interest. Rome had conquered most of its empire under the Republic (509-31 BC). In those days, a narrow elite drawn from a few noble families in the city of Rome governed the empire and considered most of its millions of inhabitants as subjects to be exploited. That was not sustainable, and the Caesars knew it. They came to power with the support of people from outside the old elite, primarily from elsewhere in Italy at first and then, later, from the whole empire. The emperors (31 BC – AD 476 in the West, centuries longer in the East) proved to be much more liberal and open-minded than their predecessors.

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The Roman Republic had granted citizenship to all the free people of Italy but only slowly and for the most part under duress. The nobles never really accepted other Italians as equals. The emperors extended citizenship to people in the provinces who supported the Roman government, first to elites, then to whole communities, and ultimately to all free inhabitants of the empire, who acquired citizenship in AD 212.

But the emperors did business with slaves and freedmen as well. As brutal as Roman slavery was it offered many more paths to manumission than American slavery did. Under some emperors, former slaves headed key government agencies. The freedman Narcissus, for example, was one of the emperor Claudius’s most powerful advisors. Another case is Caenis, an influential female secretary in the imperial family who helped stop a coup d’etat against one emperor and eventually became the common-law wife of another. She was an ex-slave.

The Roman army represented new people as well. Men from Germany, the Danube River valley or the Balkans became the backbone of the legions. Meanwhile, soldiers from Italy were in short supply. By the third century AD, as one contemporary writer put it, “The men of Italy, long unused to arms and war, were devoted to farming and peaceful pursuits.”

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Roman Emperor Constantine making a donation from the city of Rome to the Pope in support of his newfound devotion to the Christian church. (Credit: Prisma/UIG/Getty Images)

The empire was bookended, in a sense, by rulers of starkly different origins. Augustus, the first emperor, was part Roman noble; his other ancestors were wealthy Italians. The first Christian emperor, Constantine, reached the throne nearly 350 year later. His father came from what is today Serbia and his mother came from today’s Turkey. In between these two men came emperors from Spain, North Africa, Croatia, Serbia, and Syria. They reflected the diversity of the empire they had made.

The Roman Empire over the centuries welcomed new and different people, recognizing that greater strength—culturally, economically, militarily— lay with a growing populace that brought ideas, influence, and brawn. Yet, the newcomers were indeed Romans and were expected to adhere to the empire’s founding principles. The Latin language, Latin literature, basic Roman values such as honor and obedience, Roman architecture and urban planning, Roman law, and, above all, the Roman army, all endured. The immigrants changed Rome but Rome changed the immigrants in turn.

Barry Strauss, professor of history and classics at Cornell University, is a leading expert on ancient military history. His latest book is Ten Caesars: Roman Emperors from Augustus to Constantine. He is also the creator and host of the podcast ‘Antiquitas: Leaders and Legends of the Ancient World.’