Feudalism was a very rigid and stratified economic and social class system that existed in medieval Europe. Essentially it was a system where land ownership was the currency. A manor lord would grant fiefs, or tracts of land, to a nobleman in exchange for military service. This nobleman was titled as a knight. The majority of the population was bound to agricultural service to the land as a serf. Everybody was expected to swear allegiance to the king. As time went on, the tracts of land were divided up among noblemen to the extent that a very confusing system of allegiances developed in Europe. The practice of feudalism discouraged trade and nation building. Within this system, knights were to swear an oath of chivalry. This oath was focused on loyalty to the king and the Roman Catholic Church. It was a way of ensuring that the knights, who were known to be brilliant warriors, also acted with discretion and morality.