Aegisthus (; ; also transliterated as Aigisthos, ) was a figure in Greek mythology. Aegisthus is known from two primary sources: the first is Homer's Odyssey, believed to have been first written down by Homer at the end of the 8th century BCE, and the second from Aeschylus's Oresteia, written in the 5th century BCE. Aegisthus also features heavily in the action of Euripides's Electra ( 420 BCE), although his character remains offstage. Family Aegisthus was the son of Thyestes and Thyestes's own daughter Pelopia, an incestuous union motivated by his father's rivalry with the house of Atreus for the throne of Mycenae. Aegisthus murdered Atreus in order to restore his father to power, ruling jointly with him, only to be driven from power by Atreus's son Agamemnon. In another version, Aegisthus was the sole surviving son of Thyestes after Atreus killed his brother's children and served them to Thyestes in a meal. While Agamemnon laid siege to Troy, his estranged queen Clytemnestra took Aegisthus as a lover. The couple killed Agamemnon upon the king's return, making Aegisthus king of Mycenae once more. Aegisthus ruled for seven more years before his death at the hands of Agamemnon's son Orestes. Mythology Early life Thyestes felt he had been deprived of the Mycenean throne unfairly by his brother, Atreus. The two battled back and forth several times. In addition, Thyestes had an affair with Atreus's wife, Aerope. In revenge, Atreus killed Thyestes's sons and served them to him unknowingly. After realizing he had eaten his own sons' corpses, Thyestes asked an oracle how best to gain revenge. The advice was to father a son with his own daughter, Pelopia, and that son would kill Atreus. Thyestes raped Pelopia after she performed a sacrifice, hiding his identity from her. When Aegisthus was born, his mother abandoned him, ashamed of his origin, and he was raised by shepherds and suckled by a goat, hence his name Aegisthus (from , male goat). Atreus, not knowing the baby's origin, took Aegisthus in and raised him as his own son. Death of Atreus In the night in which Pelopia had been raped by her father, she had taken from him his sword which she afterwards gave to Aegisthus. When she discovered that the sword belonged to her own father, she realised that her son was the product of incestuous rape. In despair, she killed herself. Atreus in