Tell me in what year BC was the Republic established in Rome?

It was established in 509 BC. At that time, a coup d’état took place in Rome. Thus, the tsarist power was overthrown, and a republic came in its place. This is how King Lucius Tarquinius was killed. The main body of power at that time was the Republican Senate. Since then, the history of Rome has shifted into a different direction. Basically, the policy of the Senate was aimed at expanding the borders of the state, that is, at war.