John of Monte Corvino, the first missionary sent by the Pope to China, arrived in Cambaluc [medieval term for Peking] soon after Marco Polo left for Europe. John remained at Cambaluc, as head of the mission until his death in 1328. This mission became the base for other Catholic missionary work in China.
"These missionaries, spending their lives in China, learning the language and mingling with the people, must have come in contact with printed literature at every turn. John of Monte Corvino in the first dozen years of his work, even before reinforcements had arrived, had already translated the New Testament and Psalter, and prepared pictures and text for the ignorant at just the time when in China it was the natural thing to have every important literary work printed. There is no question that the Chinese who were associated in the work of translation would have suggested that the translation and the pictures should be brought before the public in what to them was the usual and natural way. Whether the missionaries agreed and thus became the first European patrons of the art of printing, we have no means of knowing. That religious image prints, prepared, like the pictures of John of Monte Corvino, 'for the ignorant,' began to appear in Europe some time within the half century after these early missionaries laid down their work, may not be altogether a coincidence" (Carter, Invention of Printing in China 2nd ed  161-62.)