Human history
A system called feudalism was a very important part of the Middle Ages. In this system, the king was at the top of the social pyramid. The king gave land to the lord in exchange for loyalty. The lords were the next in the pyramid. The lords gave land (called a fief) to knights in exchange for loyalty and protection. The knights came next in the pyramid. Peasants were not part of the feudal system because they did not give or receive land. They worked on a lord's manor in exchange for protection.