Theseus, in Greek mythology, hero of Athens; son of either King Aegeus or Poseidon. Before Aegeus left Troezen he placed his sword and sandals beneath a huge rock and told his wife Aethra that when their son, Theseus, could lift the rock he was to bring the gifts to his kingdom in Athens. At the age of 16 Theseus lifted the rock and began his journey, during which he freed the countryside of various monsters and villains (e.g., Procrustes). When Theseus arrived at Athens, Medea, then wife of Aegeus, tried to kill him. Aegeus, however, recognized the sword and sandals, saved Theseus, and exiled Medea. Theseus subsequently had numerous adventures. His most famous exploit was against the Minotaur of King Minos of Crete. Theseus insisted on being one of the seven youths and seven maidens of Athens to be sacrificed to the monster as an annual tribute. He promised his father that if he were successful in killing the Minotaur he would on his return voyage replace his ship's black sails with white ones. Ariadne, daughter of King Minos, fell in love with Theseus and gave him a magic ball of thread to be dropped at the entrance of the labyrinth; it led Theseus to the Minotaur, which he killed, and he then followed the unwound thread back to the entrance. He left Crete with Ariadne but abandoned her at Naxos. When Theseus reached home he forgot to raise white sails. Aegeus saw black sails, and, thinking his son dead, the grief-stricken father threw himself into the sea, thereafter called the Aegean. As king of Athens, Theseus instituted several reforms, most notably the federalization of the scattered Attic communities. He journeyed to the land of the Amazons, where he abducted Antiope, who bore him Hippolytus. A vengeful Amazon army invaded Athens, but Theseus defeated it. Some say Antiope died fighting beside him in the battle; others claim that Theseus killed her when she objected to his marriage to Phaedra. For helping Pirithoüs to carry off Persephone, Theseus was imprisoned in Hades until Hercules rescued him. Upon his return to Athens, he found his once great kingdom a turmoil of corruption and rebellion. He regretfully sailed away and came to rest at Skyros, where he was treacherously murdered by King Lycomedes. Although Theseus is generally thought of as legendary, the Athenians believed he had been one of their early kings.

Hero of ancient Greek legend. He was the son of Aegeus, king of Athens. On his journey to Athens, he slew many legendary villains, including Sinis, Sciron, and Procrustes. In Athens he found Aegeus married to Medea; she recognized him before her husband did and tried to poison him but failed, and Aegeus declared him heir to the throne. In Crete Theseus met Ariadne and slew the Minotaur; on returning to Athens, he forgot to replace the ship's black sail with a white one signaling his victory, and Aegeus threw himself from the Acropolis in grief. Theseus went on to unite and extend the borders of Attica. He captured the Amazon princess Antiope (Hippolyte), with the result that the Amazons attacked Athens and Antiope was killed while defending it. He abducted the child Helen and attempted to steal Persephone from Hades, but he was confined in the underworld until his rescue by Heracles. He died when the king of Scyros threw him from a cliff.

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