When Ireland was controlled by England there was a system which divided peasants from nobles called the Feudal System. In this system the king gave land to the nobles and members of the hierarchy. These people were now known as the King's vassals. These were tenants renting land from the owner. The 'granting' of the land was called feudum from which we get the word feudalism and the piece of land held by the the vassal was called a fief. When he got the land he swore an oath of homage to the king which basically meant he was a one of the kings 'men' (homme is the French for man). He promised to provide knights to the king in accordance with the amount of land received. The most important nobles were earls. They only kept some of the land for themselves called the demesne because their fief was so big. The rest was rented out to lesser nobles such as barons or knights. The earl was then like the king of his land as he had his own vassals. These vassals had peasants working on their land in return for food and shelter.