The reforms of Cleisthenes in 508/507 BCE reorganised Athens's citizen body into ten new tribes built from local demes and created a Council of Five Hundred to prepare public business. These changes gave free adult male citizens direct rule through the Assembly, where they debated and voted on law and policy in person. The system excluded women, enslaved people and resident foreigners, but within the citizen body it dispersed power widely. The Agora, the city's open central space, became the everyday venue of civic, judicial and political life.
It was the first sustained democracy and the source of much of the Western political vocabulary, from 'democracy' itself onward. It tied self-government to a physical public space, making the agora the archetype of the civic square.