In 1286 Arghun, the Ilkhan who ruled Persia, sent a request to the pope through the Nestorian monk, Rabban Bar Sauma, to send Catholic missionaries to the imperial court of Kublai (Emperor Shizu) of the Yuan dynasty of China, who was alleged to be well disposed toward Christianity.
Pope Nicholas IV received the letter in 1287 and entrusted John with the important mission to China, where about this time Venetian lay traveller Marco Polo still remained.
[1] He started on his journey in 1289, provided with letters to Arghun, to the Kublai, to Kaidu, Prince of the Tatars, to the King of Armenia and to the Patriarch of the Jacobites.
[1] From Persia they moved down by sea to India, in 1291, to the Madras region or "Country of St Thomas" where he preached for thirteen months and baptized about one hundred persons;[1][3] his companion Nicholas died.
[1] Travelling by sea from Nestorian Mailapur in Madras, he reached China in 1294, appearing in the capital "Cambaliech" or Khanbaliq (now Beijing), only to find that Kublai had just died, and Temür (Emperor Chengzong) had succeeded to the Yuan throne.
He gradually bought from the "heathen" parents about 150 boys, from 7 to 11 years of age, instructed them in Latin and Greek, wrote psalms and hymns for them and then trained them to serve Mass and sing in the choir.
A Franciscan tradition states that about 1310 John of Montecorvino converted the third Yuan monarch Külüg Khan, (Emperor Wuzong) but this is disputed.
Toghun Temür, the last Mongol (Yuan dynasty) emperor of China, sent an embassy to the French Pope Benedict XII in Avignon, in 1336.
Six centuries later, Montecorvino acted as the inspiration for another Franciscan, the Blessed Gabriele Allegra to go to China and complete the first translation of the Catholic Bible into Chinese in 1968.