ancient Rome The popular assembliesancient state, Europe, Africa, and Asia

During the republic two different assemblies elected magistrates, exercised legislative power, and made other important decisions. Only adult male Roman citizens could attend the assemblies in Rome and exercise the right to vote. The assemblies were organized according to the principle of the group vote. Although each person cast one vote, he did so within a larger voting unit. The majority vote of the unit became its vote, and a majority of unit votes was needed to decide an issue.

The centuriate assembly (comitia centuriata), as stated, was military in nature and composed of voting groups called centuries (military units). Because of its military character, it always met outside the sacred boundary of the city (pomerium) in the Field of Mars (Campus Martius). It voted on war and peace and elected all magistrates who exercised imperium (consuls, praetors, censors, and curule aediles). Before the creation of criminal courts during the late republic, it sat as a high court and exercised capital jurisdiction. Although it could legislate, this function was usually performed by the tribal assembly.

The centuriate assembly evolved through different stages during the early republic, but information exists only about its final organization. It may have begun as the citizen army meeting under arms to elect its commander and to decide on war or peace. During historical times the assembly had a complex organization. All voting citizens were placed into one of five economic classes according to wealth. Each class was allotted varying numbers of centuries, and the entire assembly consisted of 193 units. The first (and richest) class of citizens was distributed among 80 centuries; the second, third, and fourth classes were each assigned 20 units. The fifth class, comprising the poorest persons in the army, was allotted 30 centuries. In addition, there were 18 centuries of knights—men wealthy enough to afford a horse for cavalry service—and five other centuries, one of which comprised the proletarii, or landless people too poor to serve in the army. The knights voted together with the first class, and voting proceeded from richest to poorest. Because the knights and the first class controlled 98 units, they were the dominant group in the assembly, though they constituted the smallest portion of the citizen body. The assembly was deliberately designed to give the greater authority to the wealthier element and was responsible for maintaining the political supremacy of the established nobility.

The tribal assembly (comitia tributa) was a nonmilitary civilian assembly. It accordingly met within the city inside the pomerium and elected magistrates who did not exercise imperium (plebeian tribunes, plebeian aediles, and quaestors). It did most of the legislating and sat as a court for serious public offenses involving monetary fines.

The tribal assembly was more democratic in its organization than the centuriate assembly. The territory of the Roman state was divided into geographic districts called tribes, and people voted in these units according to residence. The city was divided into four urban tribes. During the 5th century bc, the surrounding countryside formed 17 rustic tribes. With the expansion of Roman territory in central Italy (387–241 bc), 14 rustic tribes were added, thus gradually increasing the assembly to 35 units, a number never exceeded.