Both boys grew up in the shadow of their father, one of Rome's greatest generals and an originally non-conservative politician who drifted to the more traditional faction when Julius Caesar became a threat.

When Caesar crossed the Rubicon in 49 BC, thus starting a civil war, Sextus' older brother Gnaeus followed their father in his escape to the East, as did most of the conservative senators.

[2] In 45 BC, Caesar managed to defeat the Pompeius brothers in the Battle of Munda, in Hispania (the Iberian Peninsula, comprising modern Spain and Portugal), after what he himself described as his hardest fought victory ever.

[3] Gnaeus Pompeius would soon die in a last stand at Lauro, but young Sextus escaped once more, this time to Sicily, and thereafter raised another dissident army in Spain.

Thus Sextus had the time and resources to develop an army, with the whole island of Sicily as his base, and (even more importantly) to establish a strong navy operated by Sicilian marines.

In the following years, military confrontations failed to return a conclusive victory for either side, although in 40 BC Sextus' admiral, the freedman Menas, seized Sardinia from Octavian's governor Marcus Lurius.

[6] Antony, the leader of Rome's eastern provinces, needed a large number of legions for the coming campaign, which would take his army (ostensibly) through Mesopotamia, Armenia and Parthia.

Octavian was defeated in the naval battle of Messina (37 BC), so he now turned to his friends Marcus Vipsanius Agrippa and Titus Statilius Taurus, both very talented generals.

Where Plutarch gives Sextus only a minor role in the confused events surrounding the fall of the Roman Republic, Appian sees him as a more central figure, who might even have emerged as the final victor, so as to establish a dynasty of Pompeys, not Caesars.