I can answer this.
The reason is God only knows there is such land called Far East until 16th Century, but he/she/it was busy to deal series family issues, mainly his/her/its children conflict such as Protestant vs Catholic, Muslim vs Orthodox and so on. Another reason was he/she/it was busying to convert pagans in New World and Southeast Asia so he/she/it had no time to care things in Far East (although he/she/it did try to convert Japanese, but apartly Shogun caught God by surprise and deal all the believer when he was busying dealing those dummie participated in Thiry Years War).
Then, around mid 19th Century finally God had time to deal Far East after most his/her/its believers/children decided not to commit genocide on eachother, so secretly God instructed a Chinese and asked him to rebel against the government, which started the Taiping Rebellion; well, God hoped his/her/its children in Shainghai would help the rebels but apartly God's messanger was broken and could not bring the message before the rebels were crushed.
So, God, despite the first attemp failed, decided to put this mission on American and sent waves after waves missionaries into China; funny enough, in the end the Heretic (Commie) crushed God's plan without any serious problems at all.
That is the brief history about God's activity in China.
