Imagine if you will, a space ship full of colonists from earth. We can accept the wormhole theory or whatever, something like Battlestar Gallactica? Now think of this:
The original planet you were scheduled to colonize is right in your path, but you cannot reach it, something has interrupted your journey and you are forced down on an uncharted but viable planet. The weather is harsh but you can adapt. The current inhabitants are close enough to humans that crossbreeding is viable.
These natives are highly psychic and can use their powers in ways humans have only ever dreamed of. After a few hundred years there are no more of the native psychics, but the people who have evolved are incredibly powerful in many ways. Mind reading, manipulation, and weapons of terrifying power have forced humanity to adopt a set of Laws to prohibit the use of weapons unless you are face to face with your enemy.
Heralding in an Age of Feudal Supremacy. Kingdoms and leaders, a varied landscape that defies the comfort of technology. Wood burning and coal are the norm. Metal is mined and forged, crops are tilled and harvested using only animals and limited machinery.
There are Seven Kingdoms, each one a separate area of the only inhabitable land mass on the planet. The seas are rough and barely navigable. Winds are too fierce to allow flying machines. No fossil fuels. A wide variety of plant life and plenty of herbal medicine to keep most people healthy.
Would anyone want to rp in this world?