The document summarizes medieval Europe, describing the Eastern Byzantine Empire which maintained Roman traditions and Greek culture after the fall of the Western Roman Empire. It then discusses Western Europe, where central government broke down, trade was disrupted, cities were abandoned, and rural populations increased, though Christianity remained influential. Feudalism developed with kings granting land to nobles who granted land to knights in exchange for military service, and knights granting land to peasants in exchange for food and labor. By 1000 CE the Byzantine Empire was losing land to Islamic Turks as stronger states emerged in Western Europe, leading to the Crusades.