Appian of Alexandria Civil Wars 5.7.65

[65] Now Octavius and Antony made a fresh partition of the whole Roman empire between themselves, the boundary line being Scodra, a city of Illyria which was supposed to be situated about midway up the Adriatic gulf. ¹ All provinces aid islands east of this place, as far as the river Euphrates, were to belong to Antony and all west of it to the ocean to Octavius. Lepidus was to govern Africa, as Octavius had given it to him. Octavius was to make war against Pompeius unless they should come to some agreement, and Antony was to make war against the Parthians to avenge their treachery toward Crassus. Octavius was to make the same agreement with Ahenobarbus that Antony had already made. Both of them might freely enlist soldiers in Italy in equal numbers. These were the last conditions of peace between Octavius and Antony. Straightway each of them sent his friends to attend to urgent business. Antony despatched Ventidius to Asia against the Parthians and against Labienus, the son of Labienus, who, with the Parthians, had made a hostile incursion into Syria and had advanced as far as Ionia during the late troubles. ² What Labienus and the Parthians did and suffered I will show in my Parthian history.