History of the Constitution of the Roman Republic
The history of the Constitution of the Roman Republic is a study of the ancient Roman Republic that traces the progression of Roman political development from the founding of the Roman Republic in 509 BC until the founding of the Roman Empire in 27 BC. The constitutional history of the Roman Republic can be divided into five phases. The first phase began with the revolution which overthrew the Roman Kingdom in 509 BC, and the final phase ended with the revolution which overthrew the Roman Republic, and thus created the Roman Empire, in 27 BC. Throughout the history of the republic, the constitutional evolution was driven by the struggle between the aristocracy and the ordinary citizens.
Ancient Rome
According to tradition and later writers such as Livy, the Roman Republic was established around 509 BC, when the last of the seven kings of Rome, Tarquin the Proud, was deposed by Lucius Junius Brutus and a system based on annually elected magistrates and various representative assemblies was established. A constitution set a series of checks and balances, and a separation of powers. The most important magistrates were the two consuls, who together exercised executive authority such as "imperium", or military command. The consuls had to work with the senate, which was initially an advisory council of the ranking nobility, or patricians, but grew in size and power.