In ancient Athens the citizens gathered in the agora, the market place, to debate the affairs of the city state and vote on them. They did that with every issue that arose, including the appointment of military commanders. It has been called the “classic” democracy. In fact, only a fraction of those living in Athens could debate and vote.
Slaves, women and foreigners had neither voice nor vote. Those citizens who made up the Athenian democracy were therefore a narrow, privileged caste, consisting of, maybe, a fifth of the population, or less.