In 509 BC the Romans changed their form of government. They ousted the kings and the republic was born. It took loosely, another year for the mechanics of the republic to be set in place.
presume you are refering to Ancient Rome, the answer then is yes and no. It was a kingdom 753 - 509BC, then a Republic 508 - 27BC then known as the Roman Empire from 27BC onwards
In descending order: 1776AD 1492AD 509BC 800BC
509BC was the date that the Romans ousted their last king and the Republic was formed.
509BC
From 753bc -509bc it was ruled by kings. 509bc-31bc it was ruled by a republic. 31bc-1453ad it was ruled by emperors.
It was when the fall of Rome happened :)
Cradle of Rome happened in 2008.
Sword of Rome happened in 2004.
Warrior of Rome happened in 1991.
Shadow of Rome happened in 2005.
Annals of Rome happened in 1986.
March on Rome happened in 1922.