The Feudal Period was a social and economic system that dominated medieval Europe, roughly from the 9th to the 15th century. It was characterized by the exchange of land for military service, where powerful lords granted land, known as fiefs, to vassals in return for loyalty and protection. This system created a hierarchy of relationships among nobles, knights, and peasants. At the bottom of this hierarchy were the serfs, who worked the land and were bound to it. The feudal system provided stability and order during a time of frequent invasions and conflicts, but it also led to a rigid class structure that limited social mobility.