quality:corruption, structural:expansion
Hellenic alliance

In 481 BC, Xerxes sent ambassadors to city states throughout Greece, asking for food, land, and water as tokens of their submission to Persia. However, Xerxes' ambassadors deliberately avoided Athens and Sparta, hoping thereby that those states would not learn of the Persians' plans. States that were opposed to Persia thus began to coalesce around these two city states. A congress of states met at Corinth in late autumn of 481 BC, and a confederate alliance of Greek city-states was formed. This confederation had powers both to send envoys to ask for assistance and to dispatch troops from the member states to defensive points after joint consultation. Herodotus does not formulate an abstract name for the union but simply calls them "οἱ Ἕλληνες" (the Greeks) and "the Greeks who had sworn alliance" (Godley translation) or "the Greeks who had banded themselves together" (Rawlinson translation). From here on, they will be referred to in this article as the 'Allies'. Sparta and Athens had a leading role in the congress but the interests of all the states influenced defensive strategy. Little is known about the internal workings of the congress or the discussions during its meetings. Only 70 of the nearly 700 Greek city-states sent representatives. Nevertheless, this was remarkable for the disjointed Greek world, especially since many of the city-states present were still technically at war with one another.