During the Medieval Times/middle ages life was dangerous, and many small kingdoms controlled by different rulers who competed for the land. Between 800-1000 CE, viking attacked Europe.
THe king gave setions of land to lords in exchange of military protection, and the Lords/Nobkes gave smaller fiets of land to knights to be their soldiers. The knights gave even more smaller sections of lans to sefs to grow their food. sefs grew food and secvices to knights for protection.