In
Greek Mythology, he was the only child of
Thyestes to survive to adulthood. Thyestes was the son of
Pelops, and the brother of
Atreus. Thyestes fell in love with Atreus' wife,
Aerope. He succeeded in making her
false to her wedding vows, but his brother found out. Atreus murdered Thyestes children and
fed them to him. Aegisthus was not fed to his father
because he had not been born yet.
Aegisthus becomes Clytemnestra's lover, after her husband, Agamemnon, son of Atreus, sacrificed Iphigenia to Artemis to ensure safe passage to Troy. When Agamemnon returns from the Trojan War, Aegisthus and Clytemnestra murder him. Aegisthus eventually dies at the hand of Orestes, son of Agamemnon and Clytemnestra.