Aeschylus

Aeschylus lived through the Persian invasions and fought at Marathon, a fact he wanted on his tombstone more than any mention of the stage. He wrote seventy to ninety plays, though only seven made it through intact, and there's still argument over whether one of those, Prometheus Bound, might actually be his son Euphorion's work. He's credited as the first to structure plays as a trilogy - the Oresteia is the only full ancient example left - and he broke form once to write about the present: The Persians deals with the war he'd just lived through, rare for Greek tragedy and the only contemporary one that survives. Aristotle said he expanded the number of characters onstage and let them clash with each other, not just the chorus. Fragments keep turning up on Egyptian papyrus, filling in gaps, but the shape of earlier tragedy is mostly reverse-engineered from what he left behind.