In Greek mythology, Aethra (also spelled Aithra; Ancient Greek Αἴθρα, "bright sky") was a Troezenian princess, the daughter of King Pittheus of Troezen. She is best known as the mother of the Athenian hero Theseus, whose father was reckoned to be either King Aegeus of Athens or the god Poseidon. In her old age she was carried off as a captive of Helen and only freed at the fall of Troy by her grandsons.
Adapted from Wikipedia, "Aethra (mother of Theseus)" · CC BY-SA 4.0
I.Family
Aethra was the daughter of Pittheus, king of Troezen. She was the mother of Theseus, whose father was reckoned to be either King Aegeus of Athens or, in some versions, the god Poseidon, and also of Clymene by Hippalces.
After her father Pittheus she was also called Pittheis.
II.Mythology: Early Life
Bellerophon once came to Troezen to ask Aethra's father, Pittheus, for her hand in marriage, but the hero was banished from Corinth before the wedding could take place.
King Aegeus, who remained childless from his previous marriages, traveled to Troezen, a city southwest of Athens. Pittheus made Aegeus drunk on unmixed wine and put him to bed with his daughter. Following instructions Athena gave her in a dream, Aethra left the sleeping Aegeus and waded across to the nearby island of Sphairia. There she poured a libation to Sphairos, the charioteer of Pelops, and lay with Poseidon during the night. In this way Aethra became pregnant by both Aegeus and Poseidon. According to Plutarch, her father spread the report of this dual parentage so that Theseus would be regarded as the son of Poseidon, whom the people of Troezen greatly revered.
Aethra later dedicated a temple to Athena Apaturia on Sphairia and renamed the island Hiera. She also established a custom among the maidens of Troezen of dedicating their girdles to Athena Apaturia on their wedding day.
When Aethra was doubly pregnant, Aegeus decided to return to Athens. Before departing he concealed his sandals, shield, and sword beneath a massive rock that served as an altar to Zeus, instructing Aethra that their grown son should move the rock and retrieve these weapons as his birthright. Theseus in time recovered these tokens and went on to become a great hero, among his deeds the slaying of the Minotaur.
III.Mythology: Enslavement and Death
When Theseus carried off the young Helen, he entrusted her to Aethra's care. Helen's brothers, the Dioscuri, recovered Helen and in retaliation abducted Aethra to Lacedaemon, where she became Helen's slave. She accompanied Helen to Troy and remained with her until she was discovered there by her grandson Acamas.
During the fall of Troy she came to the Greek camp, where her grandsons recognized her. Demophon, one of them, asked Agamemnon to secure her freedom. Agamemnon sent a messenger to Helen requesting Aethra's release, which was granted, and she regained her liberty. According to Hyginus, she later took her own life out of grief over the deaths of her sons.
Her enslavement to Helen was depicted on the chest of Cypselus and in a painting by Polygnotus in the Lesche at Delphi.