The Kingdom of Hurva has a very complicated political structure. It has many layers of governmental authority based on rank and allegiance and as such somewhat resembles the medieval feudal system. There are a number of differences, however, between the real world feudal systems of the middle ages and that of this fantasy world.
First off, perhaps it would be more accurate to describe Hurva as an empire rather than a kingdom, as the barons wield almost autonomous power within their respective baronies. Which brings us to the second big difference from the real world, which is the ordering and meaning of titles. Hurvan political titles or positions in decreasing order of station are: King , Regent (only when there is no monarch or the crown prince is not of age), Baron, Councilor, Duke, Count, Earl, Lord, Sheriff, Constable, Knight and House.
King: Claims authority via divine right. Oversees the entire kingdom including its foreign and military affairs.
Baron: Has near kingly authority of the affairs within their barony, though they owe taxes, men and fealty to the king. The king is also the Baron of Gessel, though the de facto baron throughout much of history has been the king's heir, typically the crown prince. Baron is a hereditary position.
Councilor: A member of the Privy Council (aka the King's Council). One person is appointed by each baron to sit on the Privy Council and speaks with the full authority of a Baron while at the King's Court. The council has the authority to override the king's decisions in certain areas and can do so with a simple majority vote (currently 4 votes required). A deadlocked 3-3 vote effectively freezes a course of action until one vote can be swayed. Councilors are sometimes called Representatives as well. Councilor's serve at the whim of their Baron and thus, have no set term of office nor order of succession.
Duke: The ruler of a city or town. All of the major cities are considered Duchies. The Duchy of Geston's duke tends to be a member of the royal family who is on the far outer reaches of the line of succession for the throne. Some dukes are related to either the royal family of the king or to their respective baron. Others can be granted their duchy's at the whim of the king or the baron. Ducal positions based on family ties and royal blood tend to be hereditary positions. Those titles which are granted by the duke need not be hereditary. Typically, titles which are granted are done so to great military heroes, very wealthy merchants, powerful adventurers or to those whom the baron owes a favor. Sometimes a duke will be responsible for a number of smaller villages that surround his ducal seat.
Count: In some regions called a mayor (though that is thought of as improper and a breech of ettiqutte in most locales). Counts adminster the governmental authority on the local village level. They do not have the authority to impose taxes or raise a militia as does a duke. Counts serve at the whim of their duke, although a very small number of counts hold heridtary seats due to being able to prove their heritage of royal blood.
Earl: A member of the royal family, though not of the immediate family such as cousins and nephews of the king. Can be used for an uncle of the king if succession passed on to the next generation rather than to the prior king's younger brother since he could no longer go by the title of 'Prince'. Earls hold no position within the government. It is a stricly social title. It has, in fact, come into style for Earls to simply use the title of 'Lord' instead, though there are some sticklers for tradional ettiquette so it is best to use the proper title and address when first dealing with an Earl.
Lord: Lords & Ladies are to barons as earls are to the king.
Sheriff: Responsible for all law enforcement, including the collection of taxes, in outlying areas that do not even warrant having a count oversee them. Also has limited judicial authority. They can be appointed by a duke or a baron.
Constable: The chief law enforement officer in a duchy. Appointed by the duke. Not responsible for collecting taxes or judicial descions as duchies will have other institutions to handle those things. Some dukes will extend the courtesy of the title to any number of law enforcement officials while granting the title of 'Chief Constable' to their head.
Knight: The title of knight may be bestowed upon any deemed to be a hero or protector of the realm by the king or a baron. With the permission of the king or baron, it may be bestowed by a duke. In the Barony of Gessel, this is the minimum station in order to have the right to own land. Originally the title was only bestowed upon those who were raised by some sovereign of station and trained to serve their liege in mounted combat in exchange for a land grant.
House: The term 'House (surname)' originally only applied to Royal Blooded families. House Werax, for example, is the collective family entity of the current ruling dynasty. Another usage of the term that originated in the old Kingdom of Istur however, refered to the collective entity of a wealthy merchant family. Both usages of the term are used throughout the kingdom today.