In his day, Aeschylus had published and produced more than ninety plays. Today, seven have survived. We are the fortunate beneficiaries of the complete Oresteia trilogy, telling the story of Orestes in avenging the blood of his father, and also in Zeus declaring the predominance of law, over vengeance. This theme of this emergence of, and protection of, the law is a consistent theme throughout all of Aeschylus’s plays. Many feature the question of laws and customs that exist within and between nations (cities), and how the conflicts of these customs leads to war.
The other plays are only fragments -that is, they are not complete parts of the larger trilogies and tetralogies for which they were once written: The Suppliant Maidens, The Persians, The Seven Against Thebes (a highly obscure play written as a listing of heroes featuring Oedipus and Anigone), and Prometheus Bound. Later, in Aristophanes, we find a profound defense of Aeschylus in The Frogs.