The Church of the East or Nestorian Church had a presence in China during two periods: first from the 7th through the 10th century, and later during the Mongol Yuan Dynasty in the 13th and 14th centuries. Locally, the religion was known as Jingjiao (景教).
Two possibly Nestorian monks were preaching Christianity in India in the 6th century before they smuggled silkworm eggs from China to the Eastern Roman Empire.
The first recorded Christian mission to China was led by the Syriac monk known in Chinese as Alopen. Alopen's mission arrived in the Chinese capital Chang'an in 635, during the reign of Emperor Taizong of the Tang Dynasty. Taizong extended official tolerance to the mission and invited the Christians to translate their sacred works for the imperial library. This tolerance was followed by many of Taizong's successors, allowing the Church of the East to thrive in China for over 200 years.
China became a metropolitan province of the Church of the East, under the name Beth Sinaye, in the first quarter of the 8th century. According to the 14th-century writer ʿAbdishoʿ of Nisibis, the province was established by the patriarch Sliba-zkha (714–28). Arguing from its position in the list of exterior provinces, which implied an 8th-century foundation, and on grounds of general historical probability, ʿAbdishoʿ refuted alternative claims that the province of Beth Sinaye had been founded either by the 5th-century patriarch Ahha (410–14) or the 6th-century patriarch Shila (503–23).
In 781 the Christian community in Chang'an erected a tablet known as the Nestorian Stele on the grounds of a local monastery. The stele contains a long inscription in Chinese with Syriac glosses, composed by the cleric Adam, probably the metropolitan of Beth Sinaye. The inscription describes the eventful progress of the Nestorian mission in China since Alopen's arrival. The inscription also mentions the archdeacons Gigoi of Khumdan [Chang'an] and Gabriel of Sarag [Lo-yang]; Yazdbuzid, 'priest and country-bishop of Khumdan'; Sargis, 'priest and country-bishop'; and the bishop Yohannan. These references confirm that the Church of the East in China had a well-developed hierarchy at the end of the 8th century, with bishops in both northern capitals, and there were probably other dioceses besides Chang'an and Lo-yang. Shortly afterwards Thomas of Marga mentions the monk David of Beth ʿAbe, who was metropolitan of Beth Sinaye during the reign of Timothy I (780–823). Timothy I is said also to have consecrated a metropolitan for Tibet (Beth Tuptaye), a province not again mentioned.