As I am Egypt’s queen,
Thou blushest, Antony, and that blood of thine
Is Caesar’s homager; else so thy cheek pays shame
When shrill-tongued Fulvia scolds.
(Act 1, scene 1, lines 34–37)

When Antony receives word from Octavius, who has summoned him to Rome, Cleopatra tells him he should go. Yet here her words are laced with bitter irony, indicating her anxiety that Antony may still have too strong an allegiance to Rome and so might not return to her. She interprets the blush in his cheeks as “Caesar’s homager”—that is, as a sign that Antony is little more than Octavius’s servant. Alternatively, she suggests that the blush indicates his shame at having betrayed his wife, Fulvia. Either way, Cleopatra is clearly worried that, as “Egypt’s queen,” her romance with a Roman can’t last. But Antony, who discerns her anxiety, attempts to quell her unease by rhetorically rejecting his homeland, saying: “Let Rome in Tiber melt and the wide arch / Of the ranged empire fall” (1.1.38–39).

Octavius: Contemning Rome, he has done all this and more
In Alexandria. Here’s the manner of ’t:
I’ th’ market place, on a tribunal silvered,
Cleopatra and himself in chairs of gold
Were publicly enthroned. . . .
Maecenas: This in the public eye?
Octavius: I’ th’ common showplace, where they exercise. . . .
                                She
In th’ habiliments of the goddess Isis
That day appeared, and oft before gave audience,
As ’tis reported to.
(Act 3, scene 6, lines 1–20)

Octavius relays an account he has heard about Antony, who he learns has left Athens for Alexandria. There, Antony has apparently made a public spectacle of joining Cleopatra on the Egyptian throne and declaring that his own sons will rule portions of Egypt as well as Syria, Cecilia, and Phoenicia. Octavius takes this as a threat to him since these places all lie within Rome’s broad sphere of influence. But by joining Cleopatra, who is dressed in regal garments that reference the Egyptian goddess Isis, Antony is implicitly aligning himself with the Egyptians. Hence, his contest with Octavius isn’t simply a matter of two Romans fighting it out for control of Rome. Rather, it’s a matter of Roman and Egyptian forces coming together in a clash of civilizations.

The shirt of Nessus is upon me. Teach me,
Alcides, thou mine ancestor, thy rage.
Let me lodge Lichas on the horns o’ th’ moon,
And with those hands that grasped the heaviest club
Subdue my worthiest self. The witch shall die.
To the young Roman boy she hath sold me, and I fall
Under this plot. She dies for ’t.—Eros, ho!
(Act 4, scene 12, lines 48–56)

After a heated spat about Cleopatra again betraying him in battle, Antony, onstage alone, utters these words to himself. He frames her betrayal not just as a tactical matter of having diverted her ships. Instead, he sees her as having given him up to Octavius, “the young Roman boy.” This phrasing suggests that Antony no longer sees himself as a Roman, having given up this identity to pledge himself to his Egyptian lover. Antony’s in-between status makes Cleopatra’s betrayal particularly painful, which he affirms through his reference to “the shirt of Nessus.” This reference alludes to the mythical hero Hercules, whom Antony claims as “mine ancestor.” Nessus is the name of a centaur Hercules mortally wounded, and who then deceived Hercules’s wife into giving her husband his bloodied shirt. The shirt acted as a poison that drove Hercules to madness. Antony, who is caught between his Roman and Egyptian allegiances, is similarly being driven mad.