What role did Marcus Agrippa play in Octavian’s military victories?

Marcus Vipsanius Agrippa was a pivotal military commander for Octavian (the future emperor Augustus) during the power struggles following the death of Julius Caesar. His contributions were essential to Octavian's rise to power, and it is often argued that Octavian might not have become emperor without him.1

Agrippa’s key military roles included:

• Naval Command: When Octavian struggled to defeat Sextus Pompeius at sea, Agrippa took charge. He engineered a harbor at Puteoli and secured decisive naval victories at Mylae and Naulochus in 36 BCE, effectively ending the threat from Pompeius.1
• Battle of Actium: In the climactic conflict against Mark Antony in 31 BCE, Agrippa commanded the fleet and was primarily responsible for the victory that solidified Octavian’s position.1
• Campaigns and Suppression: Agrippa served as a key commander in various theaters, including fighting against Lucius Antonius, conducting campaigns in Aquitania and on the Rhine River, and leading a distinguished military effort in Dalmatia. Later, he also successfully subdued the Cantabrians in Spain.1