IN the Hesiodic Catalogue of Women, the marriage of Helen is followed by the birth of her child Hermione which is described surprisingly as “unexpected” or “unhoped for” (ἄελπτον). The birth itself is probably not unexpected–Greek myth is not shy about connected births to sex–instead she is a metonym for the “unhoped for” destruction that issues from the union between Menelaos and Helen. After her birth, a strife rises among the gods as Zeus decides to separate the races of men and heroes and cause a great war:

Hesiod, fr. 204. 93-106

“And [Leda] gave birth to the fine-ankled Hermione in her halls,
Unhoped for, and all the gods were in diverse opinions
Because of the strife. For, then, really, Zeus, the high-thunderer was devising
Monstrous deeds, to mix up confusion on the boundless earth.
He was already hurrying to ruin the race of mortal men,
For a pretext to destroy the souls of heroes […]
Children of gods […] seeing with eyes,
But the blessed ones […] as even before
Would pursue their life and customs apart from human beings.
But [for the children] of mortals and immortals the same,
[Zeus granted…] pain upon pain…”

ἣ τέκεν ῾Ερμιόνην καλλίσφυρ[ο]ν ἐν μεγάροισιν
ἄελπτον. πάντες δὲ θεοὶ δίχα θυμὸν ἔθεντο
ἐξ ἔριδος· δὴ γὰρ τότε μήδετο θέσκελα ἔργα
Ζεὺς ὑψιβρεμέτης, †μεῖξαι κατ’ ἀπείρονα γαῖαν
τυρβάξας,† ἤδη δὲ γένος μερόπων ἀνθρώπων
πολλὸν ἀϊστῶσαι σ̣π̣ε̣ῦ̣δ̣ε̣, π̣ρ̣[ό]φασιν μὲν ὀλέσθαι
ψυχὰς ἡμιθέω[ν ….. ….. .]ο̣ι̣σ̣ι̣ βροτοῖσι
τέκ̣να θεῶν μι[…].[..]ο̣.[ ὀφ]θαλμοῖσιν ὁρῶντα,
ἀλλ̣’ ο̣ἳ μ[ὲ]ν μάκ̣[α]ρ̣ες̣ κ̣[…….]ν̣ ὡ̣ς̣ τ̣ὸ̣ πάρος περ
χωρ̣ὶς ἀπ’ ἀν[θ]ρ̣ώπων̣[ βίοτον κα]ὶ̣ ἤθε’ ἔχωσιν
το̣[..]ε̣.ε̣αλ̣[ ἀθα]νάτω̣[ν τε ἰδὲ] θ̣νητῶν ἀνθρώπων
…[ ]κ̣α̣λ ἄλγος ἐπ’ ἄλγει

Zeus’ agency and the ending of the race of heroes shows up in at least two other places in early Greek epic: Hesiod’s Works and Days and the first fragment of a poem of the Trojan War cycle called the Kypria (Cypria)

Hesiod, Works and Days, 158-165:

“Kronos’ son Zeus made a better and more just third race,
the divine generation of heroic men who are called
hemitheoi, the earlier generation on the boundless earth.
And then evil war and dread conflict wiped them out,
some of them under seven-gated Thebes, the Cadmean land,
where they struggled over the flocks of Oedipus,
and leading others in ships for booty across the sea
at Troy, for the sake of well-tressed Helen.”

Ζεὺς Κρονίδης ποίησε, δικαιότερον καὶ ἄρειον,
ἀνδρῶν ἡρώων θεῖον γένος, οἳ καλέονται
ἡμίθεοι, προτέρη γενεὴ κατ’ ἀπείρονα γαῖαν.
καὶ τοὺς μὲν πόλεμός τε κακὸς καὶ φύλοπις αἰνὴ
τοὺς μὲν ὑφ’ ἑπταπύλῳ Θήβῃ, Καδμηίδι γαίῃ,
ὤλεσε μαρναμένους μήλων ἕνεκ’ Οἰδιπόδαο,
τοὺς δὲ καὶ ἐν νήεσσιν ὑπὲρ μέγα λαῖτμα θαλάσσης
ἐς Τροίην ἀγαγὼν ῾Ελένης ἕνεκ’ ἠυκόμοιο.

Kypria, Frag. 1

“There was a time when the myriad tribes of men
wandering pressed down on the thick chest of the broad earth—
And when Zeus saw this, he pitied her and in his complex thoughts
He planned to lighten the all-nourishing earth of human beings
By fanning the great strife of the Trojan War,
So that he might lighten the weight by death. And then in Troy
The heroes were dying, and the will of Zeus was being fulfilled.”

ἦν ὅτε μυρία φῦλα κατὰ χθόνα πλαζόμεν’ αἰεὶ
βαρυστέρνου πλάτος αἴης,
Ζεὺς δὲ ἰδὼν ἐλέησε καὶ ἐν πυκιναῖς πραπίδεσσι
κουφίσαι ἀνθρώπων παμβώτορα σύνθετο γαῖαν,
ῥιπίσσας πολέμου μεγάλην ἔριν ᾿Ιλιακοῖο,
ὄφρα κενώσειεν θανάτωι βάρος. οἱ δ’ ἐνὶ Τροίηι
ἥρωες κτείνοντο, Διὸς δ’ ἐτελείετο βουλή.

A few articles about what these passages have in common with each other and other traditions:

Ludwig Koenen. “Greece, The Near East, and Egypt: Cyclic Destruction in Hesiod and the Catalogue of Women.” Transactions and Proceedings of the American Philological Association 124 (1994) 1-34.

Kenneth Mayer. “Helen and the ΔΙΟΣ ΒΟΥΛΗ.” American Journal of Philology 117 (1996) 1-15.