In Greek mythology, Aegisthus was the lover of Clytemnestra, and son of Thyestes and Pelopia. Thyestes, having a long – time rivalry with his brother and king of Mycenae, Atreus, was advised by an oracle to have a son with his own daughter, Pelopia, who would then kill his brother. Thus, Aegisthus was born. Because his mother was ashamed due to her father raping her, she abandoned the child to shepherds, and was later taken under the protection of Atreus, without knowing the child’s true identity.