archaeogeek
Banned
Is that so hard?
One of the problems is that most of the spanish kinglets were ultimately part of the house of Castille-Leon (there was an understanding during the 12th century among the christian kings that Leon had primacy as "Emperor of Spain", obviously the caliph in Cordoba rather disagreed; this changed later as well for the christians, this is also why IOTL the Portugese were annoyed at Castille-Leon-Aragon calling themselves "Spain", the idea that Spain is only this part of the iberian peninsula is an early modern concept) - so basically you'd need a dynastic POD to keep Castille and Leon from uniting and even then you still have the problem that they seem like a power bloc compared to the taifa emirates.
However, it's not really that way, under the veneer of "boot the moors out, argh!" unity there's actually a lot of intrigue going on; rebellions, murders, etc, the house of Castille-Leon was about as bad if not worse than the Plantegenets, historians I've read compare them to the Atrides basically.