OK, just a passing thought. Would it be possible to prevent rise of Spanish/Iberian/whatever identity? Say Moors are more successfull in assimilating people on Iberian pennsula and prevent rise of christian kingdoms south of Pyrenees?
So when/if reconquista happens it's by France (or "France") which means delayed and slower (HYW) and with less population to colonise it retains something of an old culture.
Just a thought, by no means thought out or realsitic.
Thoguhts? comments?