In Greek mythology, Leda (; ) was daughter of the Aetolian king Thestius, and wife of 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).