Which three periods make up the history of ancient Rome?

The history of ancient Rome is categorized into three distinct eras:1

• The regal period (753–509 bce): The era during which Rome was ruled by a series of kings.12
• The republican period (509–27 bce): The era characterized by the establishment of the republic, where power was held by elected officials rather than a monarch.13
• The imperial period (27 bce–476 ce): The era that began with Augustus as the first emperor, shifting power to an imperial form of government.13