For political reasons Antony and Cleopatra had advanced only as far as the Adriatic coast of Greece. For Antony to land on the mainland of Italy with an invading 'foreign' army would be an unsound move. This handed the initiative to Octavian who besieged the land forces and blockaded the coast. With their supply lines cut Antony attempted a breakout by sea which was unsuccessful. Cleopatra fled and Antony followed, deserting his forces. Although the struggle continued for a while this battle effectively ended Antony's chance of becoming Emperor.

Antony and Octavian had been allies in the civil war [40 to 36 bc] against Pompey the Younger. Pompey escaped from a battle with Octavian's forces but was later captured by Antony and killed.