Mithridates (mee-tree-DAHT), the king of Pontus, who has been fighting the Romans for forty years. At first, he is believed dead, but this rumor proves to be false. He is in love with Monime, a woman much younger than himself, and he is very jealous of his two sons, who are both also in love with Monime. His jealousy causes him to set up a plan whereby he can learn whom Monime really loves. In the end, he believes that both of his sons have betrayed him by joining his enemies, the Romans, and he kills himself. Before he dies, he learns that the older son has remained loyal to him, and he blesses Monime and this son.
Monime (moh-NEEM), the young woman Mithridates loves. She is in love with Mithridates’s son Xiphares, but she determines to remain faithful to Mithridates in spite of this. After he tricks her into revealing whom it is she really loves, she refuses to marry him. She tries to kill herself and is glad when Mithridates sends a servant to poison her. Monime is finally united with Xiphares, with Mithridates’s blessing.
Xiphares (gzhee-fah-REHS), Mithridates’s son, who shares his father’s feelings of enmity toward the Romans. He has been in love with Monime since the first time he met her. He says nothing about his love until his father is reported to be dead. Xiphares suffers greatly when he discovers that his brother also loves Monime and that his father, who is still alive, is returning. Xiphares finally routs the Romans and succeeds to the throne, with Monime as his queen.
Pharnace (fahr-NAHS), Mithridates’s other son, also in love with Monime. He sides with the Romans against his father. Pharnace refuses to marry the daughter of the Parthian king, with whom his father wishes to make an alliance.
Arbate (ahr-BAHT), Mithridates’s confidant, who tells him that Pharnace is in love with Monime.
Phoedime (feh-DEEM), Monime’s loyal friend and confidante.
Arcas (ahr-KAHS), a servant, charged with giving poison to Monime.