This exciting new research dates Por-Bajin, a ruined "fortress" of Uyghur Empire, to 777 AD, thus tying it to Bogu Khan & one of the most fascinating events about religious conversion in world history: the establishment of Manichaeism as a state religion. pnas.org/content/early/… 
Manichaeism was founded by Mani in Persia in the 3rd c AD. Prosecuted as a heresy in the west, it spread to China in the 7th c. Here's a manuscript of a text written in 731, explaining its doctrines & rites to a Tang emperor. But the text didn't work; in 732 it's banned in China.
The religion didn't disappear; it went underground. Here’s a tombstone discovered in 2014 in Luoyang. The owner (756-827) is a Nestorian Christian. Yet scholars suggest his grandfather&father were followers of Manichaeism. Around the time he was born, Bogu Khan arrived in Luoyang
Bogu came to Luoyang in 762 with his cavalry to help the Tang put down An Lushan rebellion. What happened there is recorded in a stele erected at the capital of Uyghur Empire: he met 4 Manichaean monks (elects); converted, he took them back & made Manichaeism the state religion.
Por-Bajin was built in 777, fifteen years after Manichaeism turned from an almost universally suppressed movement to the official religion of a powerful empire on the steppe. If it's a Manichaean monastery, it'd mark a high point in the religion's history. All suffering paid off.
Por-Bajin & its buildings were of Tang-Chinese fashion. The layout is typical of a walled palace or Buddhist temple in China. Left is the reconstruction of Por-Bajin; right are that of a Tang palace in Luoyang & painting of a monastery. All feature a grand hall in the center.
Por-Bajin means "clay house." It's characterized by rammed earth walls & wooden buildings with ceramic roof tiles - construction methods widespread in China & Central Asia but uncommon on the steppe. Lotus flowers & demonic faces were popular roof decorations in East Asia.
Therefore, Por-Bajin could've been built by or with the help of craftsmen & architects from China. After all, Bogu received enormous amount of silk from Tang court as return for his military assistance. He could hire some professionals to work for him on this magnificent project.
Unfortunately, as the research shows, the monastery was deserted soon. In 780, Bogu was killed by his minister, who took over the throne & abolished Manichaeism. It's not until 802, the religion was revived. It thrived for another 45 yrs, before the devastating invasion of Kyrgyz
Uyghurs, expelled from homeland, set up a kingdom in Qocho (Gaochang, Xinjiang) & continued to prosper for 4 centuries. They kept supporting Manichaeism. I posted some wonderful objects from this period, like an image of Mani & an illuminated letter. But it's a different story.
I’m not a specialist in Manichaeism and Uyghur Empire. If you are interested in this topic, please follow @LillaBRS @VHansenYear1000 @jae_heehan @csen_nomads. All images come from open sources online.
