The first Roman emperor, declaring himself as such in 27 B.C., was Augustus. Originally named Gaius Octavius, he emerged victorious from a series of civil wars following Julius Caesar's assassination. Augustus implemented various reforms and ushered in a long-lasting period of peace known as the Pax Romana, which significantly expanded the Roman Empire. His reign marked the transition from the Roman Republic to the Roman Empire, establishing a powerful precedent for future emperors. Augustus’s leadership transformed Rome, enhancing its administrative efficiency and promoting cultural achievements, ultimately leaving a lasting legacy on Western civilization.