Answer:
Missionaries were successful because they had more natives to fight with them.
Step-by-step explanation:
The Coahuiltecan were various small, autonomous bands of Native Americans who inhabited the Rio Grande valley in what is now southern Texas and northeastern Mexico. The various Coahuiltecan groups were hunter-gatherers. First encountered by Europeans in the sixteenth century, their population declined due to imported European diseases, slavery, and numerous small-scale wars fought against the Spanish, criollo, Apache, and other Coahuiltecan groups. The survivors were absorbed into the Hispanic and mestizo population of southern Texas or northern Mexico.