After the Greek victory against the Persians at Mycale, many Spartans believed that the war with Persia was now over. The Athenians, however, wanted to liberate ex-colonies in Ionia from Persian rule and prepared for further war with Persia by forming the Delian League. Formed in 478 BCE, representatives of many Aegean Greek city-states met on the island of Delos and were allocated different tax districts, with their payments mediated by Athens and used towards a putative war effort. Meanwhile, the Spartans stayed in the Peloponnesian League, an alliance of southern Greek states. Over the next decade the League’s treasury moved to Athens, with the taxes funding Athenian building projects. Although there were two further successful Persian-Greek battles (460 BCE and 451 BCE) several League members, ‘new allies’ who had been pressed into joining the League, revolted and asked Sparta for help against tyrannical Athens, beginning a series of wars which ended in a 30-year peace in 447 BCE.
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