It has not been asked yet. As far as ruling powers, there really isn't any. Power will be centralized by the settlements and tribes of the deserts. Faction wise, we have more then a few. There is the Servants of Light, a religious sect based out of the city of Frey. They are an anti-magic group that serve the will of the Lord of Light; believing that the Makers have turned their backs on their subjects because the masses use magic recklessly as though they are gods. They are mostly seen as crackpots though.
The Sunrunners operate as a faction of sorts, they are a power recognized by all and when someone needs help or has a job that they need done; they call on the Sunrunners guild.
The dwarves have the Iron Army of Kun Borimm, largest of the dwarven cities and considered by many to be the most advanced army to set foot in the desert. The dwarves mostly keep to themselves and don't concern themself with problems that aren't their own. They have enough on their plates with the constant attacks by gleekon war bands. There are plenty of dwarves who have left the Iron Army in search of adventure and profit, bringing with them the weapons and tools they used.
The fae have many nomadic tribes but no one truly knows how many their are or their names due to the simple fact no one has truly seen these tribes, merely heard stories.
@Scrivener