Final answer:
In 27 B.C., Augustus became the first Roman emperor, establishing the Roman Empire which signified the end of the Roman Republic.
Step-by-step explanation:
In 27 B.C., Augustus, who was called Augustus, or the "revered one", became the first Roman emperor. Augustus rose to power following Julius Caesar's assassination and through a series of political and military moves, he established the foundations of the Roman Empire. He was granted the title of Augustus by the Senate to honor his prestige and quasi-divine authority. His leadership marked the transition from the Roman Republic to the Roman Empire, which lasted until 476 CE in the West.