The settlements of the Iron Age in the territory of the Volga Region have always been particularly interesting in terms of historical science. This is justified not only by the uniqueness of this territory, but also by the formation of a substantial collection of archaeological materials. A significant number of archaeological sites of the early Iron Age have been discovered and investigated over more than half a century of archaeological research and scientific studies in the territory of the Mari Volga region. This paper introduces the main types of settlements widely spread across the territory of the Mari Volga region during the Early Iron Age. The authors discuss the causes for such innovations as the appearance of settlements in the territory of the Mari Volga region. They provide characteristics of the settlement fortifications of the Mari Volga region population of the early Iron Age. The paper addresses the issues of space organization of both fortified and unfortified settlements of the Mari Volga Region in the early Iron Age. The authors suggest that the causes for the appearance of fortified settlements are associated with both internal and external factors. This in turn influenced the construction innovations of the settlements belonging to the population of the Mari Volga region.