Orestes was the son of Agamemnon and Clytemnestra and the brother of Electra and Iphigenia. When his father returned from the Trojan War, he was murdered by Clytemnestra and her lover, Aegisthus. Orestes, who was quite young at the time, went into exile and swore to get revenge. Since it was the duty of the senior male in the house to punish the murderers, Orestes was commanded by Apollo to avenge the crime.

With the assistance of Electra and his friend Pylades, who accompanied him in all his adventures. After he reached adulthood, he returned home secretly and, plotting with his sister Electra, contrived the murder of both Aegisthus and Clytemnestra. As a consequence of his deed, Orestes was tormented by the Erinyes, or Furies, who followed him everywhere he went. The Erinyes only stopped hounding him when he sought judgement for his crime at the Aeropagus, the tribunal of Athenian judges and was acquitted.

Not all the Furies, however, accepted the verdict; and, to win full expiation from his crime, he was told to steal the sacred image of Artemis from Tauris. At Tauris he was reunited with Iphigenia and with her assistance stole the image and safely returned to Greece. It is said that he later married Hermione, the daughter of Menelaus and Helen. In the Oresteia, Aeschylus dramatized his vengeance and expiation. The story was also used by Sophocles and Euripides.

~Article courtesy of: Encyclopedia.com

~Orestes image is courtesy of George Barrie
~Oresties and Furies image is courtesy of Hellados
~Orestes-Aegisthus image is courtesy of Hellados