<P> Cleisthenes (/ ˈklaɪsθɪˌniːz /; Greek: Κλεισθένης, Kleisthénēs; also Clisthenes or Kleisthenes) was an ancient Athenian lawgiver credited with reforming the constitution of ancient Athens and setting it on a democratic footing in 508 BC . For these accomplishments, historians refer to him as "the father of Athenian democracy ." He was a member of the aristocratic Alcmaeonid clan, and the maternal grandson of the tyrant Cleisthenes of Sicyon, as the younger son of the latter's daughter Agariste and her husband Megacles . He was also credited with increasing the power of the Athenian citizens' assembly and for reducing the power of the nobility over Athenian politics . </P> <P> In 510 BC, Spartan troops helped the Athenians overthrow their king, the tyrant Hippias, son of Peisistratos . Cleomenes I, king of Sparta, put in place a pro-Spartan oligarchy headed by Isagoras . But his rival Cleisthenes, with the support of the middle class and aided by democrats, took over . Cleomenes intervened in 508 and 506 BC, but could not stop Cleisthenes, now supported by the Athenians . Through Cleisthenes' reforms, the people of Athens endowed their city with isonomic institutions--equal rights for all citizens (though only men were citizens)--and established ostracism . </P>

As a result of the reforms of cleisthenes the government of athens