What was the basis for the formation of feudal system in Western Europe in the Middle Ages?

The foundation of feudal system in medieval western Europe can be traced back to the large-scale migration of nomadic people in the late Roman Empire. During this period, the Roman Empire collapsed, the political and economic order of the European continent collapsed, and the large-scale migration of nomadic people also led to the large-scale flow of population and the redistribution of land in Europe.

In this context, farmers and free people gradually seek protection from rich and powerful nobles, providing agricultural labor and taxes in exchange for security. In order to maintain their position and power, the nobles began to gradually form their own armed forces, fought and negotiated with other nobles, and established a relatively stable political order.

With the passage of time, nobles began to consolidate their power and status by controlling land and army, and gradually developed the feudal system. The core of this system is the "feudal contract", in which nobles provide protection and services to lords at all levels through land and troops, and obtain resources such as fiefs and troops from them. This contract is not only the exchange of land and resources, but also a mutually beneficial relationship, through which political and social order is established and maintained.

Therefore, the foundation of feudal system in medieval western Europe can be summarized as three aspects: first, the political and economic chaos background in the late Roman Empire and the large-scale migration of nomadic people; Second, the nobles gradually formed their own armed forces and established a relatively stable political order under this background; Third, the nobles consolidated their power and position by controlling the land and the army, and gradually developed the feudal system.