How did Rome go from being one of many city-states in the Italian peninsula to being the center of the most powerful empire in the ancient world? Part of the answer lies in the political institutions that Rome developed early in its history. As Rome expanded its influence over more and more areas, its political institutions proved both resilient and adaptable, allowing it to incorporate diverse populations.
According to Roman tradition, the Republic began in 509 BCE when a group of noblemen overthrew the last king of Rome. The Romans replaced the king with two consuls—rulers who had many of the same powers as the king but were elected to serve one-year terms. Each consul could veto, or reject, the actions of the other consul. Although the office of consul probably did not exist in its final form until around 300 BCE, the idea behind this change—to prevent any one man from becoming too powerful—was present early on in Roman thought and shaped many of Rome’s political institutions.
Roman political institutions reflected Roman society, which was divided into two classes: the patricians, wealthy elites, and the plebeians, the common people. Initially, only the patricians were able to hold political office and make important decisions. For example, plebeians could not join the Roman Senate—an advisory body unable to create laws on its own but whose recommendations were taken seriously by the consuls. To become a senator, a Roman had to have held a political office, and plebeians could not. Over time, however, the plebeians were able to gain more influence in the political system.
Between the years 494 and 287 BCE, new political offices for plebeians were created and access to higher office, including the consulship, was opened to them. Voting assemblies and councils were established that gave plebeians more say in the politics of Rome. In 287 BCE, a law removed the last barrier to plebeian political participation by abolishing the requirement that proposed laws had to be approved by patrician senators before the Plebeian Council could consider them.
The Plebeian Council had real power and influence in Roman politics and some plebeians gained power and wealth under these new arrangements, but many remained poor. One reason that political rights did not lead to major changes was that the Comitia Centuriata—the main voting assembly that elected consuls and other important officials—was organized based on wealth. Each century—or voting group—had one vote, but the wealthy were split into smaller groups than the poor, giving the vote of a wealthy Roman more influence.