Which Roman leader defeated Cleopatra at the Battle of Actium?

The Roman leader who defeated Cleopatra at the Battle of Actium was Octavian, the future emperor Augustus. The battle took place in 31 BC during the final conflict between Octavian and Mark Antony, Cleopatra’s Roman ally and partner.

Octavian was the supreme political and military leader of the anti-Antonian side, although his experienced commander Marcus Vipsanius Agrippa played a crucial role in directing naval operations. Agrippa’s maneuvers cut Antony’s supply routes and helped force the combined Egyptian and Roman fleet into an unfavorable battle near Actium in Greece.

Cleopatra commanded a squadron of ships positioned behind Antony’s main line. When her vessels withdrew through a gap in the Roman formation, Antony followed her, abandoning much of his fleet. Octavian’s victory left him as the unchallenged power in the Roman world. He invaded Egypt in 30 BC, after which Antony and Cleopatra died and Ptolemaic rule ended.

The name “Augustus” came later: in 27 BC, the Senate granted Octavian that title as he reorganized Rome’s government and established the Roman Empire.