Tatar, a word derived from a Turanian root signifying "to pitch a tent," hence appropriate to nomadic tribes, became converted by European chroniclers into Tartar, a fanciful derivative from Tartaros (Gr. hell), and suggestive of fiends from hell. Tartary, as a geographical expression of the Middle Ages, embraced a vast stretch of territory from the Dnieper, in Eastern Europe, to the Sea of Japan; but subsequently dwindled away to Chinese and Western Turkestan.