Whether the period starting with Caesar's civil war should really be called a portion of the republic is a matter of scholarly debate. After Caesar's victory, he ruled a dictatorial regime until his assassination in 44 BC at the hands of the Liberatores. The Caesarian faction quickly gained control of the state, inaugurated the Second Triumvirate (comprising Caesar's adopted son Octavian and the dictator's two most important supporters, Mark Antony and Marcus Aemilius Lepidus), purged their political enemies, and successfully defeated the assassins in the Liberators' civil war at the Battle of Philippi. The second triumvirate failed to reach any mutually agreeable resolution; leading to the final civil war of the republic, a war which the promagistrate governors and their troops would win, and in doing so, permanently collapse the republic. Octavian, now Augustus, would be the first Roman Emperor and would transform the oligarchic Republic into the autocratic Roman Empire.