The first emperor of Rome was Augustus, originally known as Gaius Octavius. He was the adopted heir of Julius Caesar and rose to power after a series of civil wars following Caesar's assassination in 44 BC. Augustus became the first Roman emperor in 27 BC, marking the beginning of the Roman Empire and the end of the Roman Republic. His reign brought significant reforms, including administrative efficiency, expanded infrastructure, and relative peace known as the Pax Romana. Augustus set the foundation for future emperors and transformed Rome into a dominant power in the ancient world.