In Greek mythology, Leucothea (Greek: Leukothea (Λευκοθέα), "white goddess") was one of the aspects under which an ancient sea goddess was recognized, in this case as a transformed nymph.
In the more familiar variant, Ino, the daughter of Cadmus, sister of Semele, and queen of Athamas, became a goddess after Hera drove her insane as a punishment for caring for the newborn Dionysus. She leapt into the sea with her son Melicertes in her arms, and out of pity, the Hellenes asserted, the Olympian gods turned them both into sea-gods, transforming Melicertes into Palaemon, the patron of the Isthmian games, and Ino into Leucothea.
In the version sited at Rhodes, a much earlier mythic level is reflected in the genealogy: there, the woman who plunged into the sea and became Leucothea was Halia ("of the sea", a personification of the saltiness of the sea) whose parents were from the ancient generation, Thalassa and Pontus or Uranus. She was a local nymph and one of the aboriginal Telchines of the island. Halia became Poseidon's wife and bore him Rhodos and six sons; the sons were maddened by Aphrodite in retaliation for an impious affront, assaulted their sister and were confined beneath the Earth by Poseidon. Thus the Rhodians traced their mythic descent from Rhodos and the Sun god Helios.
In the Odyssey (5.333 ff.) Leucothea makes a dramatic appearance as a gannet who tells the shipwrecked Odysseus to discard his cloak and raft and offers him a veil (κρήδεμνον, kredemnon) to wind round himself to save his life and reach land. Homer makes her the transfiguration of Ino. In Laconia, she has a sanctuary, where she answers people's questions about dreams. This is her form of the oracle.
Leucothea is mentioned by John Milton in the Paradise Lost scene where archangel Michael descends to Adam and Eve to declare that they must no longer abide in Paradise (second edition, 1674, book XI, lines 133-135):
To resalute the World with sacred light,
Leucothea is mentioned by Robert Graves in The White Goddess.
In Ezra Pound's Cantos, she is one of the goddess figures who comes to the poet's aid in Section: Rock-Drill (Cantos 85–95). She is introduced in Canto 91 as "Cadmus's daughter":
As the sea-gull Κάδμου θυγάτηρ said to Odysseus
"get rid of parap[h]ernalia"
She returns in Cantos 93 ("Κάδμου θυγάτηρ") and 95 ("Κάδμου θυγάτηρ/ bringing light per diafana/ λευκὁς Λευκόθοε/ white foam, a sea-gull... 'My bikini is worth yr/ raft'. Said Leucothae... Then Leucothea had pity,/'mortal once/ Who now is a sea-god...'"), and reappears at the beginning of Canto 96, the first of the Thrones section ("Κρήδεμνον.../ κρήδεμνον.../ and the wave concealed her,/ dark mass of great water.").
Leucothea appears twice in Dialoghi con Leucò (Dialogues with Leucò) by Cesare Pavese.
Leucothoé was the first work by the Irish playwright Isaac Bickerstaffe published in 1756.
Leucothea becomes a metaphor, in Marcel Proust's In the Shadow of Young Girls in Flower, for the mist that covers a young man's gaze when looking on the beauty of young women: "...a cloud that had re-formed a few days later, once I had met them, muting the glow of their loveliness, often passing between them and my eyes, which saw them now dimmed, as through a gentle haze, reminiscent of Virgil's Leucothea."
A similar name is carried by two other characters in Greek mythology.Leucothoë: a princess, daughter of Orchamus and sister of Clytia, Leucothoë was loved by Helios, who disguised himself as Leucothoë's mother to gain entrance to her chambers. Clytia, jealous of her sister because she wanted Helios for herself, told Orchamus the truth, betraying her sister's trust and confidence in her. Enraged, Orchamus ordered Leucothoë, who claimed Helios had forced her to succumb to his desires, buried alive. Helios changed Leucothoë's lifeless body into an incense plant. Helios refused to forgive Clytia for betraying his beloved, and a grieving Clytia wilted and slowly turned into a heliotrope, which follows the sun every day.
Leucothoë, one of the Nereids.