Final answer:
Spanish missionaries settled in St. Augustine and nearby areas for religious conversion and spreading Christianity. They established mission villages among indigenous populations and worked to Christianize and acculturate them.
Step-by-step explanation:
Spanish missionaries left their homelands to settle in St. Augustine and nearby areas primarily for religious conversion and spreading Christianity. The Spanish believed it was their duty to bring Catholicism to the native peoples of the Americas. They established mission villages among the indigenous populations, such as the Guale, Timucua, and Apalachee Indians, and worked to Christianize and acculturate them. These missions also served as a source of labor and food, as well as a buffer between British settlements and Spanish territories.