Thetis
（Θέτις). A daughter of Nereus and Doris. She was the wife of Peleus, by whom she became the mother of Achilles ( Il. i. 538 Il., xviii. 35; Theog. 244). As a goddess of the sea she dwelt, like her sisters the Nereids, below the waves with her father, Nereus. She there received Dionysus on his flight from Lycurgus, and the god, in his gratitude, presented her with a golden urn ( Il. vi. 135; Od. xxiv. 75). When Hephaestus was thrown down from heaven, he was likewise received by Thetis. She had been brought up by Heré, and when she reached the age of maturity, Zeus and Heré gave her, against her will, in marriage to Peleus. Such was the Homeric story ( Il. xviii. 85 Il., 432); but later accounts add that Poseidon and Zeus himself first sued for her hand; but when Themis declared that the son of Thetis would be stronger than his father, both gods desisted from their suit, and desired her marriage with a mortal (Isthm. viii. 58). Chiron informed his friend Peleus how he might gain possession of her, even if she should metamorphose herself: for Thetis, like Proteus, had the power of assuming any form she pleased; and she had recourse to this means of escaping from Peleus, who, instructed by Chiron, held the goddess fast till she again assumed her proper form, and promised to marry him ( Nem. iii. 60). This story, which appears first in Pindar, was a favourite subject in vasepainting of an early date. The wedding of Peleus was honoured with the presence of all the gods, with the exception of Eris or Discord, who was not invited, and who avenged herself by throwing among the assembled gods the apple which was the source of so much misery. (See Paris.) For the action of Thetis in the story of her son, see Achilles.