Trade is not China's sole basis of contact with the West.

Since the thirteenth century, Roman Catholic missionaries have been attempting to establish their church in China.

Although by 1800 only a few hundred thousand Chinese have been converted, the missionaries—mostly Jesuits—contribute greatly to Chinese knowledge in such fields as cannon casting, calendar making, geography, mathematics, cartography, music, art, and architecture.

The Jesuits are especially adept at fitting Christianity into a Chinese framework and are condemned by a papal decision in 1704 for having tolerated the continuance of Confucian ancestor rites among Christian converts.

The papal decision quickly weakens the Christian movement, which it proscribead as heterodox and disloyal.