The social structure of the Roman Empire was complex, stringent and hierarchical. The nature of the social classes was based on economic and political factors. Despite the demanding requisites for entry into the upper classes, there was a relative degree of mobility in Roman society.
At the top of the Roman social structure was the senatorial class. To become a senator, a man had to have a fortune equal to at least 1 million sesterces. Senators were not allowed to participate in trade, public contracts or any other form of non-agricultural business. The elite group within the senatorial class was known as the nobility. Nobles were men who were elected consul or whose ancestry included at least one consul.
Below the senatorial class was the equestrian class, men with a fortune of at least 400,000 sesterces. Equestrians could participate in the economic activities prohibited to senators. The commons were Roman citizens who were not of the equestrian or senatorial class. They could marry any other Roman citizen, and their children were Roman citizens as well.
Latins were freeborn residents who did not have full citizenship rights (until 89 B.C.). Freedpeople, or freedmen, were former slaves formally freed by their masters; they could apply for citizenship. Although they could not hold public office, their children could hold office. Slaves were at the bottom of the Roman social structure. They were considered property.