Answer:
Greed
Step-by-step explanation:
Spain's settlement of the New World did appear to have some religious undertones to it, at least at the beginning. But, I think overall it was really for just greed. I think all of the reasoning they gave for wanting to conquer was just covering up the fact that they just wanted to get their first. Like with any case of imperialism, all any country wants is to have control over much more land than other countries. Not to mention the new items and materials discovered, which probably sold for a high price. I also think there is a part of us human beings, that are always striving to expand and find more beyond what we know, but that's a whole other topic entirely.