Because Spain would be ahead of all the others
There were actually several times in history that american indians became allies with english colonists and fight other american indians, but the most significant was during the French and Indian war.
Zulu was dispersed into 13 chiefdoms comprised of these at the bottom. At least I believe I’ve searched and went through old paperwork and documents for this but this is what sounds like your question is asking let me know if it helped .
Christianity was the official religion of the Roman empire