"It is unclear, even to the discerning scholar, how much time passed, but, using evidence and logic, it can be determined that it must have been a fair amount: when the Cilanese Narti appeared in Isumbras they were colonists, fleeing some manner of oppression certainly, but a peaceful oppression (if such a thing exists); when the Narti who would become the Iskandrans came into the region, they were surely refugees from some kind of war or aggression, and thus, their state was much more desperate. On the other hand, the Cilanese colonies had had ample time to develop their civilization and culture enough to act as they did next.

"As the to-be Iskandrans moved south, finding some hope in the lush land of their kinsfolk, the Cilanese colonists, who had over the years become severe isolationists, closed their borders and forcibly repelled the migration of the Iskandrans. Of course they did not know it, but their actions at that time would lead to one of the major currents of action that would mark the history of the region. Pushed to their limit, the Iskandrans were forced to turn west onto the barren moors and, with every step, their tempraments hardened and became more bitter."

It seems clear that the shock of encountering the Netherwild, and the resources required to defend against its malice, must have contributed to the Cilanese response. History is always wont to villify, but there are always reasons behind actions, and I've found, more often than not, those actions are selfish, but not overtly evil.