King

As with most nobility, only your lineage really matters. The heir ascends on the throne upon his predecessor's death or abdication, and rules until he or she decides to follow suit. And unlike more tolerant nations, no queen can ever be the sole ruler of lands in Eire - only men are allowed to claim a vacant throne.   The matter of choosing a successor is a rather interesting one however. They still follow the ancient Eirish law of having the youngest descendant of the ruling family as heir, provided he is at least twelve years old. Why choose a mere boy over an experienced man? Historically, it was explained by how few Hummish survived their exodus from the continent. Having more kids means having younger kids, which increases their chances to take the throne. Nowadays? Mostly a way to weaken the kings' authority, I think.

Two types of people rule the lands of Eire together - a mighty king and a humble bureaucrat.

In contrast to their humble origins, the Eirish kings hold the full dominion over all public affairs on their land. Not to the same level as near-divine Ardenian emperors, but with much less opposition. How so? Well, there is no offical heretary nobility in the Kingdom of Eire. Instead, all their affairs are governed by numerous well-educated officials in the service of a king. A large body of very specific laws helps "guide the ship of state", as they say.   Or so it is on paper. In practice, the Eirish nobility still exists. It is just called differently. Certain government positions are all but reserved for members of a specific family, most often based on the recommendations from a currently serving official. And those are some very powerful positions too, at times rivaling the kings themselves in influence. As for lower ranks... Do you seriously believe they are appointed based on one's merit alone and not their lineage or influence within the Eirish society?