The book provides an opportunity to look at the events of the XIII century that took place in the vastness of Eurasia, not only from a military-political or religious, but also from a trade and economic point of view. The reader is offered an overview of the relationship of the Roman Catholic Church with the Mongol khans against the background of the confrontation between Christianity and Islam in the cross wars. It shows the development of trade relations between East and West, the receipt by merchants of additional profits as a result of the conquests of the Mongols. Since the Russian principalities were at the center of the events, the author offers his vision of the relationship between the Russian princes and the Russian Orthodox Church with the Roman Catholic Church during the Tatar-Mongol invasion. For a wide range of readers interested in history.