What class did cleisthenes come from and what kind of power did this group exercise over athenians?

I think that Cleisthenes of Athens, Cleisthenes also spelled Clisthenes, (born c. 570 BCE—died c. 508), statesman regarded as the founder of Athenian democracy, serving as chief archon (highest magistrate) of Athens (525–524). Cleisthenes successfully allied himself with the popular Assembly against the nobles (508) and imposed democratic reform. Perhaps his most important innovation was the basing of individual political responsibility on citizenship of a place rather than on membership in a clan.
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