For three centuries the Church in colonial Spanish America was the primary cultural institution affecting the lives of all Spain's overseas subjects. Education, charity, art, architecture, all the humane arts had been the legacy of the Church as well as its greatest gift to the New World, the Christianization of the Indians. In all these pursuits the Church was ably and dutifully supported by the Crown. Concurrently, clerics of all ranks and occupations were tied closely to the civil authority by the Royal Patronage.
The achievements of the orders of the Church were out of proportion to their numbers. Franciscans, Dominicans, Mercedarians, then Jesuits and others all left their mark on Spanish America and often expanded the empire through missionary activities. Paraguay, an isolated province in the Río de la Plata, was a striking example of the successful toil of various orders. However, in 1767 by command of the regalist Carlos III, the Jesuits were expelled from this region (and the entire empire) and at the turn of the century there remained but three orders in the province, Franciscans, Dominicans, and Mercedarians. Of the three the Franciscans were the most important in the colonial era. Ever since the 1530's, this order was concerned with the conversion and welfare of the Indians. Reductions of the Guaraní were established by the Franciscans long before those of the better known Jesuits. Among the great figures of the Franciscan first century in Paraguay were Fray Martín Ignacio de Loyola and especially fray Luis de Bolaños, the “Apostle of Paraguay.”