Catholic missionaries

Missionary work of the Catholic Church has often been undertaken outside the geographically defined parishes and dioceses by religious orders who have people and material resources to spare, and some of which specialized in missions. Eventually, parishes and dioceses would be organized worldwide, often after an intermediate phase as an apostolic prefecture or apostolic vicariate.

The New Testament missionary outreach of the Christian church from the time of St Paul was extensive throughout the Roman Empire.

During the Middle Ages Christian monasteries and missionaries such as Saint Patrick and Adalbert of Prague propagated learning and religion beyond the boundaries of the old Roman Empire. In the seventh century Gregory the Great sent missionaries, including Augustine of Canterbury, into England. The Hiberno-Scottish mission began in 563.

In the late thirteenth and early fourteenth centuries, Franciscans such as William of Rubruck, John of Montecorvino, and Giovanni ed' Magnolia were sent as missionaries to the Near and Far East. Their travels took them as far as China in an attempt to convert the advancing Mongols, especially the Great Khans of the Mongol Empire. (Also see Catholic Church in China.)

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