Medieval empires were powerful political entities that dominated Europe, Asia, and parts of Africa from the 5th to the late 15th century. These empires, such as the Holy Roman Empire and the Byzantine Empire, were characterized by feudal systems where land was held by nobles in exchange for military service. The social structure was hierarchical, with kings at the top, followed by lords, knights, and peasants. The rise and fall of these empires were influenced by various factors, including warfare, trade, and cultural exchanges. The Mongol Empire, for instance, expanded rapidly across Asia and Europe, reshaping the political landscape. These empires left a lasting legacy on modern nations and cultures.