Book excerpt: Aeschylus was a Greek playwright considered to be the founder of the tragedy. Aeschylus along with Sophocles and Euripides are the three major Greek tragedians whose plays have survived. Before Aeschylus, characters in a play only interacted with the chorus. Aeschylus expanded the number of actors allowing for interaction among the characters. Seven of his 92 plays have survived. The Persian invasion of Greece, which took place during his lifetime, influenced many of his plays. The Oresteia is a trilogy of Greek tragedies written by Aeschylus, which concerns the end of the curse on the House of Atreus. The plays were "Agamemnon," "Choephorae" (The Libation-Bearers), and the "Eumenides" (Furies).