Koinon

Koinon (Greek: Κοινόν, pl. Κοινά, Koina), meaning "common," in the sense of "public," had many interpretations, some societal, some governmental. The word was the neuter form of the adjective, roughly equivalent in the governmental sense to Latin res publica, "the public thing." Among the most frequent uses is "commonwealth," the government of a single state, such as the Athenian.

Frequent in the historical writings is a sense of "league" or "federation" an association of distinct city-states in a sympoliteia. As government of a league, koinon comprised such functions as defense, diplomacy, economics, and religious practices among its member states. The word was carried over to other political associations in mediaeval and modern Greek history.

In Epirus itself there had in ancient times existed the Koinon of the Molossians. There was a Lacedaemonian League, centred on Sparta and its old dominions for a period under Roman rule, a Koinon of the Macedonians, also under Roman rule. In modern Greek history, during the Greek War of Independence, a local self-government termed Koinon was set up in the islands of Hydra, Spetsai and Psara.

Some federations termed Koinon were:

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