What type of ruler ship ancient rome did an have?

Rome had a monarchy for 144 years, followed by a republic for 482 years, and by personal rule by one man for 503 years. Historians have called the personal ruler emperor, but the Romans did not use this term. They have also divided the period of personal rule into the Principate (personal rule presented as benign) which lasted for 311 years, and a Dominate (a more autocratic personal rule) which lasted for 192 years.