The Roman Republic is the period of the ancient Roman civilization in which the government operates as a republic.

It begins with the overthrow of the Roman monarchy, traditionally dated around 508 BCE, and its replacement by a government headed by two consuls, elected annually by the citizens and advised by a senate.

A complex constitution gradually develops, centered on the principles of a separation of powers and checks and balances.

Except in times of dire national emergency, public offices are limited to one year, so in theory at least, no single individual can dominate his fellow citizens.In practice, Roman society is hierarchical.

The evolution of the Constitution of the Roman Republic is heavily influenced by the struggle between Rome's landholding aristocracy (the patricians), who trace their ancestry back to the early history of the Roman kingdom, and the far more numerous citizen-commoners, the plebeians.

Over time, the laws that give patricians exclusive rights to Rome's highest offices are repealed or weakened, and a new aristocracy emerges from among the plebeian class.

The leaders of the Republic develop a strong tradition and morality requiring public service and patronage in peace and war, meaning that military and political success are inextricably linked.

During the first two centuries of its existence, the Republic expands through a combination of conquest and alliance, from central Italy to the entire Italian peninsula.

By the following century it includes North Africa, the Iberian Peninsula, Greece, and what is now southern France.

Two centuries after that, towards the end of the 1st century BCE, it includes the rest of modern France, and much of the east.

By this time, despite the Republic's traditional and lawful constraints against any individual's acquisition of permanent political powers, Roman politics is dominated by a small number of Roman leaders, their uneasy alliances punctuated by a series of civil wars.The final victor in these civil wars, Octavian (later Augustus), reforms the Republic as a Principate, with himself as Rome's "first citizen" (princeps).

The Senate continues to sit and debate.

Annual magistrates are elected as before, but final decisions on matters of policy, warfare, diplomacy and appointments are privileged to the princeps as "first among equals" (or imperator due to the holding of imperium, from which the term emperor is derived).

His powers are monarchic in all but name, and he holds them for his lifetime, on behalf of the Senate and people of Rome.

The Roman Republic is never restored, but neither is it abolished, so the event that signals its transition to Roman Empire is a matter of interpretation.

Historians have variously proposed the appointment of Julius Caesar as perpetual dictator in 44 BCE, the defeat of Mark Antony at the Battle of Actium in 31 BCE, and the Roman Senate's grant of extraordinary powers to Octavian (Augustus) under the first settlement in 27 BCE, as candidates for the defining pivotal event ending the Republic.Many of Rome's legal and legislative structures can still be observed throughout Europe and the rest of the world by modern nation state and international organizations.

The Romans' Latin language has influenced grammar and vocabulary across parts of Europe and the world.