Nella mitologia greca Leda era figlia di Testio e moglie di Tindaro, re di Sparta.
La leggenda narra che Zeus, innamoratosi di lei, si trasformò in un cigno e si accoppiò con Leda, che generò due uova. Da un uovo sarebbero usciti i Dioscuri, Castore e Polluce, mentre dall’altro Elena e Clitennestra.
La tradizione mitica è discordante riguardo a quale fosse la progenie divina; secondo alcune versioni i figli immortali di Zeus non sarebbero stati i Dioscuri (“figli di Zeus”), ma Polluce ed Elena, mentre gli altri due sarebbero figli di Tindaro.
Secondo un’altra versione del mito, Leda trovò l’uovo, frutto dell’unione tra Zeus e Nemesi, dal quale sarebbe uscita Elena.
In Greek mythology, Leda (Ancient Greek: Λήδα) was daughter of the Aetolian king Thestius, and wife of the king Tyndareus (Τυνδάρεως) of Sparta. Her myth gave rise to the popular motif in Renaissance and later art of Leda and the Swan. She was the mother of Helen (Ἑλένη) of Troy, Clytemnestra (Κλυταιμνήστρα), and Castor and Pollux (Κάστωρ καὶ Πολυδεύκης, also spelled Kastor and Polydeuces).
Leda was admired by Zeus, who seduced her in the guise of a swan. As a swan, Zeus fell into her arms for protection from a pursuing eagle. Their consummation, on the same night as Leda lay with her husband Tyndareus, resulted in two eggs from which hatched Helen (later known as the beautiful “Helen of Troy”), Clytemnestra, and Castor and Pollux (also known as the Dioscuri (Διόσκουροι). Which children are the progeny of Tyndareus, the mortal king, and which are of Zeus, and are thus half-immortal, is not consistent among accounts, nor is which child hatched from which egg. The split is almost always half mortal, half divine, although the pairings do not always reflect the children’s heritage pairings. Castor and Polydeuces are sometimes both mortal, sometimes both divine. One consistent point is that if only one of them is immortal, it is Polydeuces. It is also always stated that Helen is the daughter of Zeus.