[@Cyclone] Perhaps you could've raided Dieuporteille once, and met their match against some of the finest knights? Especially given the religious ferocity of the Dieuporteillean knights, it's likely they would've done their best to drive back these heathens. 

Could be even that they were the ones that pushed them away from the southern provinces -- explaining why they didn't venture too far down.

Of course it'd be weird if I only said how I beat you, so if you have suggestions for things your people could've done to mine, I'm open to that.