A FEUDAL SOCIETYThe Normans introduced the hierarchical feudal system. This was a pyramidal system that had to head the king, under the king there were the barons and under them there were knights. The peasants can be divided into two categories: the villains, the freedom who had land, and serfs, who had no land. The feudal system was structured around the principle of the concession of lands and it based essential on agrarian economy. William the conqueror decided to create a register in which recorded the possessions of his population. In this way he hoped to know how much money he could collect in terms of taxes. The result of this survey were written in a register called Domesday book.