ヴォルガ・ブルガール
Though not attested in any document, the town of Kozmodemyansk was likely preceded by a Mari wooden fortress controlling the confluence of the Volga and the Vetluga Rivers. It was also an important resting and trading place for traders from the North who traveled along the river to Volga Bulgaria. The Mongol invasion of Volga Bulgaria was a serious blow to the region.