The Greek name Orestes derives from two ancient words. The first word means mountain. The second word means to stand. Ancient scholars believed the combined meaning was stands on a mountain. This linguistic root connects the figure to the House of Atreus in Greek mythology. He is also known by the patronymic Agamemnonides. That title translates directly to son of Agamemnon. Harry Thurston Peck recorded this definition in his Harpers Dictionary of Classical Antiquities published in 1898. Robert Graves noted that obscure threads of much older works remain within these myths. These stories retain the core identity of the character across centuries.
Homeric Narratives
Orestes stood absent from Mycenae when his father returned home. Agamemnon brought the Trojan princess Cassandra as his concubine into the palace. Aegisthus murdered Agamemnon while Orestes remained away from the city. Seven years passed before the young man returned from Athens. He avenged his father's death by killing both Aegisthus and Clytemnestra. Homer held up Orestes as a favorable example for Telemachus. Penelope suffered under the pressure of suitors just as Electra did. Pindar offered a different version where a nurse named Arsinoe saved him. His sister Electra conveyed him out of the country when Clytemnestra wished to kill him. The boy escaped to Phanote on Mount Parnassus. King Strophius took charge of him during those early years of exile.Aeschylean Trial
Madness seized Orestes after he killed his mother. The Erinyes pursued him relentlessly with their duty to punish family violations. He sought refuge in the temple at Delphi but found no protection there. Apollo had ordered the killing yet could not shield him from consequences. Athena received him on the Acropolis of Athens to arrange a formal trial. Twelve judges including herself heard the case before them. The Erinyes demanded their victim while Orestes asserted he acted on Apollo's orders. Athena voted last announcing her support for acquittal. The votes counted evenly forcing an acquittal under stipulated rules. The Erinyes converted into Eumenides offering wisdom and counsel instead of punishment. A new ritual established them as Venerable Goddesses worshipped by the people.