Chadcidian Conf., AR Tetradrachm, 4th Century BC (21mm, 14.46g)

The Chalcidian League (Greek: Κοινόν τῶν Χαλκιδέων, Koinon tōn Chalkideōn, "League of the Chalcidians"), also referred to as the Olynthians^[1] or the Chalcidians in Thrace (Χαλκιδεῖς ἐπί Θρᾴκης, Chalkideis epi Thrakēs)^[2] to distinguish them from the Chalcidians in Euboea,^[3] was a federal state that existed on the Chalcidice peninsula, on the shores of the northwest Aegean Sea, from around 430 BCE until it was destroyed by Philip II of Macedon in 348 BCE.

There are two theories on the origins of the Chalcidians:

Harrison's theory has been rejected by some historians such as Bradeen (1952) but has been adopted by other historians, such as U. Kahrsted (1953) and M. Zahrnt (1971).^[6] N. G. L. Hammond (1992) notes the uncertainty about the tribe's origins but concludes that, at least, "The discovery that there was Submycenaean, Protogeometric, and Geometric pottery in Chalcidice like that of southern Greece, and sometimes having connections with Lefkandi, makes it certain that Chalcidice and southern Greece were in contact with one another".^[7]