The Eumenides

Along with Sophocles and Euripides, Aeschylus (circa 524-455 B.C.) is one of the triumvirate of Ancient Greek playwrights responsible for much of the establishment of Western drama as it exists today. Aeschylus was the first whose work survived and is credited as the Father of Tragedy, though the other two are probably better known in the West today. He was famous even among his contemporaries; Aristotle mentions how he revolutionized plays by creating more characters and having them interact with each other to produce conflict.
Some of the Ancient Greeks' most famous characters are famous because of Aeschylus, none more so than Orestes. Aeschylus is believed to have written nearly 100 plays, but less than 10 survived, chief among them being the trilogy known as "The Oresteia," consisting of the three tragedies "Agamemnon," "The Libation Bearers" and "The Eumenides." He's also credited for "Prometheus Bound," though the authorship of that one is still in dispute.