the Peloponnesian War was only in its fourth year. His plays often express pride in the achievement of the older generation (the victors at Marathon) yet they are not jingoistic, and they are staunchly opposed to the war with Sparta. The plays are particularly scathing in criticism of war profiteers, among whom populists such as Cleon figure prominently. By the time his last play was produced (around 386 BC) Athens had been defeated in war, its empire had been dismantled and it had undergone a transformation from being the political to the intellectual centre of Greece. Aristophanes was part of this transformation and he shared in the intellectual fashions of the period—the structure of his plays evolves from Old Comedy until, in his last surviving play, Wealth II, it more closely resembles New Comedy. However it is uncertain whether he led or merely responded to changes in audience expectations. Aristophanes won second prize at the City Dionysia in 427 BC with his first play The Banqueters (now lost). He won first prize there with his next play, The Babylonians (also now lost). It was usual for foreign dignitaries to attend the City Dionysia, and The Babylonians caused some embarrassment for the Athenian authorities since it depicted the cities of the Delian League as slaves grinding at a mill. Some influential citizens, notably Cleon, reviled the play as slander against the polis and possibly took legal action against the author. The details of the trial are unrecorded but, speaking through the hero of his third play The Acharnians (staged at the Lenaia, where there were few or no foreign dignitaries), the poet carefully distinguishes between the polis and the real targets of his acerbic wit: Aristophanes repeatedly savages Cleon in his later plays. But these satirical diatribes appear to have had no effect on Cleon's political career—a few weeks after the performance of The Knights—a play full of anti-Cleon jokes—Cleon was elected to the prestigious board of ten generals. Cleon also seems to have had no real power to limit or control Aristophanes: the caricatures of him continued up to and even beyond his death. In the absence of clear biographical facts about Aristophanes, scholars make educated guesses based on interpretation of the language in the plays. Inscriptions and summaries or comments by Hellenistic and Byzantine scholars can also provide useful clues. We know from a combination of these sources, and