- the ancient Roman state from the expulsion of the Etruscan monarchs in 509 bc (see Tarquinius) until the assumption of power by Augustus (Octavian) in 27 bc .
The republic was dominated by a landed aristocracy, the patricians, who ruled through the advisory Senate and two annually elected chief magistrates or consuls; the plebeians or common people had their own representatives, the tribunes, who in time gained the power of veto over the other magistrates. During the life of the republic Rome came to dominate the rest of Italy and, following the Punic and Macedonian Wars, began to acquire extensive dominions in the Mediterranean and Asia Minor. Dissatisfaction with the Senate’s control of government led to civil wars, which culminated in Julius Caesar’s brief dictatorship. This established the principle of personal autocracy, and after Caesar’s assassination another round of civil war ended with Octavian’s assumption of authority