How long was rome a republic when did julius caesar become the first emperor of rome?

Rome became a republic after expelling the Etruscan king, in 509 BCE. Caesar returned from his victorious civil war campaigns to reign supreme in Rome, albeit briefly, in 45 BCE. So the republic lasted approximately 464 years from the time of its inception to its essential end. But historians often date the end of the republic and onset of the Empire or Principate, at 27 BCE. (In other words, Augustus is often considered the first emperor.)So technically the republic lasted about 482 years.