If someone introduced himself as Gaius Sempronius Rutilus in AD 118 but wasn’t wearing a toga, could you tell if he was a Roman citizen?
A senator in his toga, a sign of Roman citizenship
There were four classes of people in the Roman Empire: citizens of Rome (cives), Latins, noncitizens or peregrines (peregrini), and slaves. Latins enjoyed some but not all of the privileges of a civis. The privileges were many and ranged from the opportunity to participate in Roman politics to being exiled instead of fed to the beasts in an arena for the same crime. Perhaps nothing illustrates the advantage better than the different fates of the apostles Paul (a Roman citizen) and Peter (a Judaean peregrine). When executed by command of Nero, Paul was beheaded while Peter was crucified.
Proof of citizenship was provided by having your name appear on the census-list, which was updated every five years during the Republic. After AD 4, a policy of birth registration was established. A copy could be obtained for proving one’s age, very much like the birth certificates of today.
During the early Republic, a Roman citizen used two names: a given name (praenomen) and a clan name (nomen). During the time of Sulla (80’s BC) the three-part name (tria nomina) where a family name (cognomen) was added after the nomen became common. During the late Republic and the Empire until AD 212, the three-part name was a sign of Roman citizenship. It became a criminal offense in AD 24 to adopt the tria nomina if a man was not a citizen; it was treated as a type of forgery.
The tri nomina was not the only obvious sign of citizenship. Although not all citizens wore a toga, only a citizen could legally wear one.
Who could be a Roman citizen?
Merely being born in a Rome did not make you a Roman citizen (civis). The status of your parents decided the matter. If your parents were citizens, so were you, even if they decided to abandon you at birth (a common practice with unwanted children, especially girls).
In many ways, a freed slave enjoyed a relationship with the former master much like that of parent and child. If a slave was freed by a Roman citizen, he became a citizen with some limitations on his rights to engage in politics, but his children were citizens with full rights.
Adoption by a Roman citizen conferred all the rights of a child born in a legally recognized Roman marriage, but only if the adoptee was already a citizen. In Lew Wallace’s novel, Ben Hur: A Tale of the Christ, Quintus Arrius, the Roman admiral, would have had to first arrange for manumission (freeing) of Judah ben Hur by a Roman citizen (himself or another), which would give Judah his citizenship. Then Quintus could adopt and give Judah his own name. If Judah had been a free man, Arrias could not have adopted him because he was not already a citizen.
In the 1st century BC, the free inhabitants of Rome and Italy were Roman citizens. At various locations around the Empire, retired legionaries were given land in the provinces, establishing colonial towns (coloniae). Philippi in Greece is one example. Since Roman citizenship was a requirement to serve in a legion, the residents of a colonia were mostly Roman citizens. Residents of some other cities (municipia) were given citizenship by special grant of the emperor.
The emperor could grant citizenship to anyone. This might involve bribery of someone at court who would make the request, but this “selling” of citizenship was not reported to be common except during the rule of Claudius. One documented case in that time period is the tribune who told the apostle Paul that he had paid a lot of money to become a citizen.
Being the child of a Roman citizen was not necessarily enough to make you one. Your parents had to have a Roman law marriage (iustae nuptiae or iustum matrimonium) where both parents possessed conubium, the right to contract a legally recognized marriage. All Roman citizens had that, and some others were granted that right. An exception was the child of a citizen mother fathered by a slave or an unknown father. In that case, the child was a Roman citizen. It was very common for a child with a Roman citizen father not to be a citizen. Citizens often fathered children with their slaves, and having a slave mother made the child a slave. A father could make a male child a citizen by freeing him and adopting him. No provision was available in Roman law to make an illegitimate daughter into a citizen.
One certain (although not easy) way for a peregrine to become a citizen was to enlist in the Roman military. The auxiliaries (auxiliae) were infantry units of noncitizens that were organized like the legions. After serving an enlistment of 25 years, the retiring auxiliary soldier was granted Roman citizenship. Service for 26 years in the Roman navy earned citizenship as well. In addition to receiving citizenship themselves, their children born while they were in service (when an official marriage was forbidden) also became citizens.
During the later Empire, almost all free persons were granted citizenship through a decree by Caracalla.
Where you live and what you are
It was common for a Roman citizen to also be a citizen of the location where he or she lived. Such dual citizenship carried a price. A person could be required to fulfill the civic duties of either or both. The apostle Paul is one example, being both a Jew of the tribe of Benjamin and citizen of Rome.
Residing in a location, no matter how long, only made you a permanent resident (incola). Such persons had to obey the laws of both their place of residence and their city or country of citizenship.
Aldrete, Gregory S. Daily Life in the Roman City: Rome, Pompeii, and Ostia. Westport, CT: Greenwood Press, 2004.
Crook, J. A. Law and Life of Rome, 90 BC.―A.D. 212. Ithaca, NY: Cornell University Press, 1967.
Image of the Roman senator is from the Walters Art Museum, Baltimore, MD.