大秦景教流行中国碑
After Alopen's time, the Church of the East was prominent in China for the remainder of the Tang Dynasty's power. Different emperors treated it differently, with some showing it the tolerance it received in the early decades, and some openly persecuting it. Nestorianism disappeared with the fall of the Tang Dynasty in the early 10th century. It did not return for three centuries, when it was reintroduced by the Mongols. The story of Alopen became prominent again in the 17th century, when the Nestorian Stele was rediscovered and the Chinese were surprised to find that the "new" religion being preached by the missionaries, had actually been in existence in China more than 10 centuries earlier.