Actium was a battle fought in 31 BC between the forces of Octavian and Mark Antony. The battle was won by Octavian, who was later known as Augustus Caesar, and it marked the end of the Roman Republic and the beginning of the Roman Empire. Agrippa was a Roman general and statesman who served under Octavian and was instrumental in his victory at Actium. He was a close friend and advisor to Octavian and was one of the most important figures in the transition from the Roman Republic to the Roman Empire.