You might have other knights who got the title but did not get the land, and to complicate things further, any of these characters can have multiple titles. For example, this duke might also be knighted. Now, it's worth noting that these titles of nobility, duke, count, baron, earl, these tended to be hereditary. You would pass it down from one generation to the next as long as the next generation pledged fealty to their lord. The title knight, however, was given for service and did not tend to be passed down from generation to generation, and to be clear, these still aren't all the actors here. You also have the church, which during medieval times was a very powerful institution. At the top of the church, you had the Bishop of Rome, also known as the pope, and you had their bishops in significant regions.