Answer
Sextus Pompey, the son of Pompey the Great, was defeated by Agrippa, the general of Octavian (later Augustus), in the battles of Mylae and Naulochus. These naval battles took place in 36 and 36 BC, respectively, and were part of the Roman civil war between Octavian and Pompey. Agrippa's victories secured control of the Mediterranean Sea for Octavian and ultimately led to his victory in the war.