The city of Athens during the classical period of Ancient Greece (508–322 BC) was the major urban center of the notable polis (city-state) of the same name, located in Attica, Greece, leading the Delian League in the Peloponnesian War against Sparta and the Peloponnesian League. Athenian democracy was established in 508 BC under Cleisthenes following the tyranny of Isagoras.