From the time of Innocent III. Roman Catholic writers boast of the missionary zeal of the mendicant orders. They are spoken of as most assiduous in visiting prisons, hospitals, and places of imminent peril, in caring for the spiritual wants of the poor; and that they were also the most active servants of the church in the propagation of Christianity among remote and savage nations. So far this appears to have been the case in the thirteenth and fourteenth centuries; but as all history goes to prove, that these mendicants were the most zealous agents of the Holy See in all its ambitious schemes and worst practices throughout Christendom, it is difficult to give them credit for pure christian zeal. From the methods they pursued and the results of their missions, it is more than obvious that they had chiefly in view their own advancement or the extension of the papal sovereignty. Still, there may have been pious men amongst them, who were animated by higher motives, and labored with disinterested devotion; and as the vices of the mendicants in general are notorious, we should be glad to record all the good of them we can.
From the time of the religious wars of Charlemagne to the exterminating wars in Languedoc, the Roman missionaries usually preached the gospel of peace at the head of an army headed by bishops, and laid the pathway for its reception open by the sword; but in the thirteenth century, pious missionary bands of Dominicans and Franciscans were sent by the Roman pontiffs to the Chinese, the Tartars, and the adjacent countries. Large numbers among these nations professed the christian faith. John of Monte Corvino, a Franciscan, was distinguished by the success of his labors; and in 1307 Clement V. erected an archiepiscopal see at Cambalu, that is, Pekin, the modern capital of China. The same pontiff sent seven other bishops, also Franciscans, into those regions; and this distant branch of the hierarchy was carefully nourished by succeeding pontiffs. "So long as the Tartar empire in China continued, not only the Latins, but the Nestorians also had liberty to profess their religion freely all over northern Asia, and to propagate it far and wide. But that most potent emperor of the Tartars, TimurBec, having embraced Mahometanism, persecuted with violence and the sword all who adhered to the Christian religion. The nation of the Tartars, in which such numbers once professed Christianity, universally submitted to the Koran. Thus the christian religion was overthrown in those parts of Asia inhabited by the Chinese, the Tartars, the Moguls, and other nations, whose history is yet imperfectly known. At least no mention has been found of any Latin Christians resident in those countries, subsequent to the year 1370. But of the Nestorians living in China, some traces can be found, though not very clear, as late as the sixteenth century."
Among the European princes, Jagello, duke of Lithuania, Poland, was nearly the only one that still adhered to the idolatry of his ancestors. And he, in the year 1386, embraced the christian rites, was baptized, and persuaded his subjects to do the same thing. What remains there were of the old religions in Prussia and Livonia, were extirpated by the Teutonic knights and crusaders with war and massacres. In Spain the Saracens still held the sovereignty of Granada, Andalucia, and Murcia; and against them the christian kings of Castile, Arragon, and Navarre, waged perpetual war; and, though with difficulty, triumphed, and became sole masters of Spain in the fifteenth century under the reign of Ferdinand and Isabella.