‘Men make the city, not walls or ships,’ Thucydides wrote in his History of the Peloponnesian Wars. The physical polis was merely the stage for the institutions and laws of politeia. The men who made it were not the same as the mass they governed. The vast majority of Athenian residents were excluded from political participation on the grounds of sex and birth. If the Roman Empire was more generous with citizenship, it was because popular political participation had expired with the republic.