The Persian Wars allowed to Greece to gain considerable power and prestige, create a great Empire due to the establishing of the Delian League. History is strewn with alliances and pacts that change with political ambition, power struggles internal and external which change with time; as we are witnessing today with the collapse of the Soviet Empire, emergence of Putin and China onto the global stage. The rise and decline of Athens, Persia and Sparta and emergence of Macedonia involved many such alliances, pacts between states. By 478 BC Athens emerged as the dominant power with Sparta disadvantaged despite being the dominant force in the Delian League not helped by internal strife and a devastating earthquake ,resulting in asking Athens help. It was the resulting consequence of involving Athens that a further 30 years of skirmishes between them which neither gaining the upper hand. The Second Peloponnesian War as the Greek historian Thucydides who lived through these events states
:what made war inevitable was the growth of Athenian power and the fear this caused in Sparta: The constant power struggles and alliances, skirmishes resulted in both Athens and Sparta being weakened undermining both. Athens second attempt to take Sicily was a disaster Thucydides......for they(Athenians) were utterly defeated; their sufferings on an enormous scale, army navy, everything was destroyed and out of many only a few returned. This defeat in Sicily was the turning point in this Peloponnesian War. From 413 BC the war was no longer a struggle between Athens and Sparta as others saw it as an opportunity to get involved and gain an advantage among them the Persians. Athens had internal political strife, suffered a coup but democracy emerged again and began to re assert her power between 410-407BC but alas, did not last. By 406BC and many naval defeats Sparta yet again