Nestor,
I understand your quest to be straight philosophy or history; however, I'll recommend some of the more well known playwrights. I've always found that fiction of a period can provide historical insight, particularly regarding political and social moods.
Aeschylus, Euripides, Sophocles, Aristophanes, Plautus and Terence. Seneca also wrote plays, but has already been mentioned for his other work.
I understand your quest to be straight philosophy or history; however, I'll recommend some of the more well known playwrights. I've always found that fiction of a period can provide historical insight, particularly regarding political and social moods.
Aeschylus, Euripides, Sophocles, Aristophanes, Plautus and Terence. Seneca also wrote plays, but has already been mentioned for his other work.