Mount & Blade Seria How To Defeat The Nords Faction In Mount&Blade?

How to defeat the Nords faction in Mount&Blade? - mount & blade seria

I conquered all areas north. Well, in the north had apparently not knowing where to go. My questions are, why are still active in the maps and numbers do not seem to decrease, no matter how often I train? Is this a bug in the game? If so, a solution for this? Thank you for your quick response. Best regards.