Mongol Empire. It covered almost all of Eurasia, and only on the territory of Hungary were the Mongols stopped, forcing them to turn back, but even then they managed to retain all the lands they had previously conquered. This medieval empire is considered by many as an undoubted historical phenomenon. Research into it has been undertaken several times. The fundamental work of the great Russian scientist N.Ya. Bichurin (Iakinthos) is considered throughout the world a classic work on the history of the Mongols.