Feudalism was the system around which the primary social structure of the Middle Ages was organised. As practised, individual nobles, rather than the ruling monarch would be charged with the management of various vassals. Farmers who committed to an oath of loyalty to a lord would receive a grant of land, known as a fief. In return, vassals had to agree to military duty. Upon the death of a vassal, the fief automatically went to his heir, but only if homage was renewed with the ruling noble. In addition to military duty, the vassal was obliged to help the lord in official matters, such as administering justice, contributing money, and attending the lord at court. As a vassal, he must also house the lord and his entourage when travelling across his grant of land. These visits could be quite a burdensome undertaking since royal travellers and their companions could easily bankrupt a vassal. In return for their services, it was the lord's responsibility to protect the vassal.

Though not technically slaves, Serfs, possibly derived from the Roman word coloni, did the work on the lord's manor and were bound to a lord for life. They could not marry without the lord's permission and could own no property. In addition to servitude, serfs were bound to land that they worked and could not leave it. If a serf was able to run away and managed to stay in a distant town for a year and a day, he would be free. Serfs were also offered protection from the lord, but they did not have to agree to military service. Serfs lived very harsh lives were work was hard and rewards were few.