Cleisthenes’ Ten-Tribe Reform and Council of 500 Established

Athens had just shaken off a tyranny and was struggling to define itself. Cleisthenes, an Alcmaeonid with elite pedigree, faced Isagoras in a bitter contest over the city’s future. Herodotus says that, losing ground, Cleisthenes “made common cause with the people” and proposed something no rival could match: remake the Athenians themselves [1]. The old four Ionian tribes would be broken. Ten new tribes would carry new names, new heroes, and, most importantly, new rules of belonging.

In 508/7 BCE, the city took that leap. Ten tribes replaced four, a change Aristotle’s Athenian Constitution confirms and explains: Cleisthenes “distributed the whole population into ten tribes” and increased the Council to 500 seats—50 from each tribe [4]. The demes, local communities recorded on stone, became the basis of citizenship. Neighborhood registers mattered more than ancestry. And the tribes were mixed across three territorial trittyes—city, coast, inland—so that fishermen at Phaleron, potters near the Kerameikos, and farmers around Marathon shared civic fate [16].

The mechanics were simple and radical. Each tribe supplied 50 councillors to the Boule, selected yearly, and these 50 took turns as the prytaneis, the presiding committee, eating on duty beneath the round, white-plastered Tholos in the Agora [18]. The Council prepared business for the Assembly; the Assembly met on the stony slope of the Pnyx to declare war, approve alliances, and pass decrees [17]. In Herodotus’ prose—plain as unpainted marble—you can hear the iron-on-stone scrape as new tribal names were cut and the old vanished [1].

Names mattered. The ten eponymous heroes stood bronze and scarlet in painted reliefs; their boards in the Agora displayed draft decrees and notices. The tribes were no longer kin clubs; they were engines for decision-making. The Council of 500 could now represent the breadth of Attica: Alopeke to Aegaleos, Sunium’s azure cape to the inland fields of Acharnai. The new roster forced aristocratic factions to compete in public, where the sound was debate rather than dagger.

It was more than a redistricting. It was a theory of power. By multiplying tribes and posts, Cleisthenes made capture harder and participation routine. Aristotle is explicit about the motive—expand participation and dilute the old clubs [4]. And by tying citizenship to deme registers, the city could administer oaths, scrutinies, and pay in a way a kin-based order could not. The Council’s 500 seats turned a few dozen power-brokers into hundreds of rotating stewards.

The change didn’t end Athens’ troubles. Spartan intervention soon followed, and foreign entanglements multiplied [2]. But something irreversible had happened in the civic heart of the city. In the Bouleuterion just west of the Royal Stoa, scarlet ceremonial ropes would one day sweep latecomers toward the Assembly. The system could move crowds now—by law, by sound, by stone.

In the weeks after the reforms, new demotic names appeared in public records; lists of 500 councillors were posted tribe by tribe. The Pnyx, already a place of gathering, became the routine theater of sovereignty. The Council began issuing probouleumata—preliminary proposals—for Assembly debate [18]. What changed first was not a single law but a rhythm: agenda set in the Boule, decision by show of hands on the Pnyx, execution and scrutiny back in the Agora.

The stakes were obvious to friend and foe. Isagoras’ strategy—rule with Spartan help—now required reversing visible, popular changes. Cleisthenes’ strategy—embed power in procedures—had a different weapon: permanence. Names on stone endure. And they echo. The new tribes would supply jurors, sailors, magistrates, and soldiers. The experiment had its frame. What the city would paint inside it—navy, empire, pay, and oaths—was coming next.