Monty Python and the Holy Grail forever gave us the perfect test for whether or not someone is the king: see if he’s got fecal matter all over him. Presumably, the kings behind the official kingdoms of Chronicles of Elyria will themselves be free of such refuse, allowing them to focus more upon tasks like keeping down the poor, executing those who do not kneel in deference, and arranging peasant houses in the shape of naughty words.
But why speculate? You can jump into the recruitment channels and threads for the various launch kingdoms to sign up as a loyal vassal well ahead of the game’s launch. It’s perfect for nobles who enjoy politicking, aspiring nobles who enjoy politicking (or backstabbing) until they’re no longer simply aspiring, and peasants who wish to protest that lobbing around very large Kickstarter donations is no basis for a system of governance. (Let us know how that last one works out for you.)