Mount and Blade could be what you're looking for, except you have to earn your status as a monarch first.

It's a medieval action RPG with no fantasy elements where you raise a group of warriors that follow you around from peasants and villagers into knights. There's no story and once you get a strong enough warband you can take a castle for yourself and start your own grasroots faction to compete with the six that are already in the game

it's awesome