The Normans introduced the feudal system to England. According to this system, the king owned all the land and others could hold land in exchange for providing services to the king.
William the Conqueror appointed barons who were provided with estates taken from the original English earls. In return, the barons paid him taxes and supplied soldiers for his armies.
The barons, in turn, let their knights hold smaller sections of land, while the knights left part of this land to people called villeins. They were farmers who had to provide some of their produce to the local lord of the manor. In this way, the land and the whole of England society was broken into small, easily controlled units.