The Matienians (Ancient Greek Language: Ματιηνοί, Matienoi) are a people mentioned by Herodotus as located west of the Halys River (book 1.75), in the 18th satrapy of the Persian Empire together with the Saspeirians and the Alarodians (book 3.94), situated between the Armenians and the Cissians (book 5.52), and as related to the Ligyans, the Mariandynians and the Cappadocians (book 7.72).
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Matienians Wikipedia(Text) CC BY-SA