Feudalism, the prevailing form of political organization in western and central Europe from 900 to 1300. After the fall of the Roman Empire in the fifth century A.D. it had become increasingly difficult for any government to rule effectively over a large area. Feudalism—a special method of local, rather than central, government—saved Europe from anarchy.

Feudal government depended on personal agreements between a number of individuals who possessed military power. These individuals usually had landed estates. They owed loyalty not to a nation, but only to those individuals with whom they had made agreements. The methods by which they received the products of their estates and ruled their workers constitute another aspect of feudalism, called the manorial, or seignorial, system.

Many historians believe that the term feudalism cannot be restricted to the government of medieval Europe. Russia, China, the Byzantine Empire, India, and, particularly, Japan had at certain times institutions resembling those of European feudalism.