[@Catchphrase] Unfortunately we have already created all the houses for the various Kingdoms. Ideally it would be best if you created a individual character. Though if you really want to create a nation I could make something work:

a) you could create a island kingdom located somewhere off the coast of Formaroth and you could create a completely new kingdom

b) you could choose one of the already existing kingdom's and edit about with it (though this will restrict you with your choices)

c) you could create a house within an already existing kingdom and try and start a civil war/ rebellion.

You can check the map and already existing kingdoms on the reference page: http://www.roleplayerguild.com/topics/89216-formaroth-battle-for-the-throne-reference-sheet/ooc#post-3203217