Helen of Troy refuge with Leda. The swan gained her affection, and the two mated. Leda then produced an egg, from which Helen emerged. The First Vatican Mythographer introduces the notion that two eggs came from the union: one containing Castor and Pollux; one with Helen and Clytemnestra. Nevertheless, the same author earlier states that Helen, Castor and Pollux were produced from a single egg. Pseudo-Apollodorus states that Leda had intercourse with both Zeus and Tyndareus the night she conceived Helen. On the other hand, in the "Cypria", part of the Epic Cycle, Helen was the daughter of Zeus and the goddess Nemesis.
Zeus been hidden by Gaia. Together, Zeus, his brothers and sisters, Hecatonchires and Cyclopes overthrew Cronus and the other Titans, in the combat called the Titanomachy. The defeated Titans were then cast into a shadowy underworld region known as Tartarus. Atlas, one of the titans who fought against Zeus, was punished by having to hold up the sky. After the battle with the Titans, Zeus shared the world with his elder brothers, Poseidon and Hades, by drawing lots: Zeus got the sky and air, Poseidon the waters, and Hades the world of the dead (the underworld). The ancient Earth, Gaia, could