How did missionaries spread Roman Catholicism around the world?

The spread of Roman Catholicism globally was a complex process driven by religious zeal, European exploration, and colonial expansion. Beginning in the 15th century, Catholic monarchs in nations like Portugal and Spain accepted responsibility for evangelizing newly encountered peoples under royal patronage systems known as patronato real or padroado.12

Missionary work was primarily carried out by religious orders, including Franciscans, Dominicans, and Jesuits. These missionaries traveled widely, building churches and establishing missions—central buildings for religious and educational work. In the Americas, this often occurred alongside military conquest, while in Asia, Jesuits like St. Francis Xavier and Matteo Ricci sought to establish communities through education, training local clergy, and sometimes engaging with local cultures and rites.13

To coordinate these efforts, the papacy established the Congregation for the Propagation of the Faith in 1622 to provide oversight, training, and policy direction. While early efforts were often tied to imperial interests, missionary activity continued to evolve, eventually emphasizing the development of indigenous clergy and, following the Second Vatican Council, a focus on dialogue.124