I don't think Spain was regarded as particularly inherently holy land by Christians. Or most of the land that had either been conquered by or was under threat of conquest from Islamic rulers. Which was pretty much everywhere. I think it's inaccurate to split religious dominion from any other kind of dominion, particularly for those religions in those days (and to this day with Islam). Religion, politics, laws and customs are often a package deal and were very much a package deal for both those religions at that time.