Xerxes king of Persia, having been often discomfited by the Greeks, his power began greatly to decline; which Artabanes, commander of the royal guards, perceiving, he entertained the hopes of sacrificing to his ambition, not only Xerxes, but all the royal family, and by that method to ascend the throne of Persia; for which purpose, availing himself of the advantage which his familiarity and friendship with the king gave him, he entered, at dead of night, the apartment of Xerxes, and slew him.

He afterwards so irritated the young princes against one another, that Artaxerxes, one of the said princes, caused his brother Darius to be slain, believing him the parricide, by the artful insinuations of Artabanes.

Now nothing was wanting to complete his treasonous designs, but the death of Artaxerxes; which Artabanes having prepared, though by various accidents delayed, (which furnish the episodical ornaments of this drama) he could not accomplish it, the treason being discovered, and Artaxerxes preserved; which discovery and preservation form the principal action of the ensuing drama.

Justin, lib. 3, cap. I.