But it's fun to make guesses that will later on turn into ideas. So...
Idea 1: The Dundar Empire could be an ancient civilization that died out long ago, but we later on face some ghosts of them, more powerful ghosts, as they lived long, they should be more powerful so as to show why they lived so long.
Idea 2: The Dundar Empire could be a civilization up north, who we might get help from, or face in combat.