According to Wikipedia, a Chalcidian type helmet was a helmet made of bronze and was worn by ancient warriors of the Hellenic world, especially popular in Greece in the fifth and fourth centuries BC. The helmet was also worn extensively in the Greek (southern) parts of Italy in the same period. Scholars think that the one found in Ukraine may have belonged to certain regiments of Darius the Great’s army during his invasion into the territory of Scythia (area of present-day Ukraine). “Royal Scythia, Greece, Kyiv Rus” book has details of the campaign.
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