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The Nereid Thetis in Greek Mythology

Thetis and Achilles

In Greek mythology it is almost unheard of for a mortal to overshadow their immortal parent; but in the case of Thetis, the sea goddess and mother of Achilles, that is just what happened.

The Family Line of Thetis

Thetis was a minor sea goddess, the daughter of Nereus, the god of the Aegean Sea, and the Oceanid Doris; via her mother. Thetis was the granddaughter of Oceanus and Tethys. As an offspring of Nereus, Thetis was classed as one of the 50 Nereids.

Thetis and Amphitrite were the most prominent of the Nereids in Greek mythology, although the basic role of the Nereids was simply to be companions of the Olympian sea god, Poseidon.

"Poseidon and the Nereids" by Friedrich Ernst Wolfrom (1857-1920) PD-art-70

"Poseidon and the Nereids" by Friedrich Ernst Wolfrom (1857-1920) PD-art-70

Thetis in Ancient Stories

The story of Thetis would evolve over time, and the Nereid would gain the attributes of shape-shifting, as well as foresight; and Thetis would start to appear as an individual in ancient stories.

Hephaestus – Thetis appears in the story of Hephaestus, the metalworking god. Hephaestus was thrown from Mount Olympus, either by Hera or Zeus, and fell into the sea near the island of Lemnos. Hephaestus was rescued by Thetis and the Oceanid Eurynome, and transported to Lemnos. On the island, Hephaestus made beautiful objects for his rescuers, until the beauty of his work made him worthy of a position on Lemnos.

Dionysus – It was also Thetis who offered refuge to Dionysus when the god of wine was driven out of Thrace. This occurred during the rule of King Lycurgus, when the cult of Dionysus was banned by the king. Dionysus’ place of safety proved to be a seaweed bed inside Thetis’ undersea grotto.

Zeus – Thetis seemed to have an affinity for helping the Olympian gods, and she even aided Zeus, the supreme deity. Zeus’ position was threatened on one occasion when Hera, Poseidon and Athena plotted against him. Hearing of the plot, Thetis dispatched the Hecatonchire Briareus from his Aegean palace, to sit alongside Zeus; so fearsome was Briareus that any idea of an uprising was quashed.

It is in stories associated with the Trojan War that Thetis is most prominent.

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Jan Sadeler (1550–1600) PD-art-70

Jan Sadeler (1550–1600) PD-art-70

The Wedding of Thetis and Peleus

One of the starting points for the Trojan War was said to be the wedding of Thetis and Peleus. The story of how Peleus came to marry Thetis is a fascinating one.

As a companion of Poseidon, the beauty of Thetis attracted both the sea god and his brother Zeus. Before either Poseidon or Zeus could act on their impulses, the Titanide Themis made a prophecy that the son of Thetis would be greater than the father.

Neither Zeus nor Poseidon wanted a son more powerful than themselves, and so Zeus decided that the only option was for Thetis to be married off to a mortal; even if Thetis’ son was more powerful than his father, that son would be no match for Zeus.

Zeus decided that Peleus, a former Argonaut and hunter of the Calydonian Boar, would be an ideal mate for Thetis; Thetis though had no desire to be married to a mortal, and so spurned Peleus’ advances.

Zeus then sent Chiron, the wise centaur, to advise Peleus about how to make Thetis his wife. Peleus had to trap Thetis, and bind her tight, so that she could not escape if she changed shape. When she found she could not escape, Thetis agreed to become Peleus’ wife.

A marriage ceremony was arranged, and nearly all of the gods were invited to the festivities on Mount Pelion, where the Muses and Apollo entertained. The celebration though was interrupted when Eris, the goddess of strife, who had not been invited, threw amongst the guests, the Golden Apple of Discord.

The marriage of Peleus and Thetis though would produce one child; a son by the name of Achilles.

Thetis Immerses Achilles. Antoine Borel (1743-1810) PD-art-70

Thetis Immerses Achilles. Antoine Borel (1743-1810) PD-art-70

Homer's Iliad from Amazon

The Young Achilles

Thetis was upset to find that Achilles was mortal like his father, and so she set about trying to make Achilles immortal. The main story about the Nereid seeking to achieve this would see Thetis covering her son in ambrosia, before placing Achilles in a fire to burn away his mortal parts. Thetis did not tell Peleus of her plan, and when Peleus discovered Achilles being burnt, he was horrified; Thetis dropped Achilles and fled, never to return to the home of Peleus.

A more famous version of this story sees Thetis dipping the baby Achilles into the River Styx, to imbue him with immortality. Most of Achilles’ body was therefore made invulnerable, but the heel by which Thetis had held the baby was not immersed in the water, and so a weak spot was left.

Peleus would place his son in the care of Chiron for tutoring, but Thetis would return to the life of her son as the Trojan War was about to start. It had been foretold that Achilles would either live a long and dull life or would have a shorter, glorious one.

Thetis wishing for her son to live a long life hid Achilles away in the court of King Lycomedes, where the boy was disguised as a girl. When Odysseus came to the court in search of Achilles, the disguise was easily seen through, when Achilles was tricked into choosing armour over female finery.

Thetis Gives Achilles his Armour. Giulio Romano PD-art-70

Thetis Gives Achilles his Armour. Giulio Romano PD-art-70

Thetis in the Trojan War

With Achilles on the way to Troy, Thetis tried to protect her son as much as possible, and so the Nereid has Hephaestus manufacture magnificent armour for her son.

During the fighting, Thetis did not intervene to help her son, although when Agamemnon and Achilles fight, Thetis asks Zeus to punish Agamemnon and the Achaean forces. Zeus agrees to the request, and the Trojans make significant advances.

Shortly afterward, when Achilles rejoins the fight, the prophecy about Achilles comes true, for the Greek hero is killed by Paris, the Trojan prince. Achilles' life has been short and glorious.

Thetis leads her sisters in the mourning of her deceased son, and when the time comes, it is Thetis who moves the body of Achilles, as well as that of his friend Patroclus, to their final resting place upon the White Island.

The time of heroes was drawing to an end, and with the death of Achilles, the story of Thetis also comes to an end.