On the morning after the banquet given in honor of Aeneas, Dido confides to Anna, her sister, that the Trojan warrior is the only man she has met since the death of her husband, Sychaeus, who could make her consider breaking her vow to remain faithful to his memory and never remarry. Urging the queen to act on these new, amorous feelings, Anna emphasizes that the dead do not care about the romantic lives of those they leave behind. She advises Dido to pursue the Trojan, both for the sake of her own happiness and for the future safety and prosperity of Carthage, which, Anna says, will be militarily strengthened by the Trojans's remaining presence. Anna's counsel increases Dido's lust for Aeneas, but, unable to act on this passion, the queen languishes helplessly, neglecting her once-paramount project, the half-built new city of Carthage.
Dido and Aeneas's relationship catches the attention of Juno and Venus. For very different reasons — Juno wants to delay Aeneas's reaching Italy, and Venus wants to ensure his safety — the two goddesses jointly conspire to bring about a sexual union of the pair. While Aeneas and Dido are out hunting one day, Juno causes a torrential storm, and the pair seeks shelter in a cave, where they are sexually united. Dido tries to legitimatize the union by calling it a marriage.
News of the relationship spreads throughout Africa. King Iarbas, one of Dido's rejected suitors, vents his anger in a prayer to Jupiter, who sends Mercury to Aeneas to remind the Trojan leader that he is shirking his heaven-appointed duty to found a new homeland: Aeneas must sail from Carthage at once. Shocked into action by Jupiter's command, Aeneas gives secret orders for the ships to be made ready to sail, deciding to postpone notifying Dido of his intention to leave Carthage until the right occasion presents itself.
