Nestorian Turks

The Nestorian branch of Christianity was the first major schism, as far as I know. Due to being declared heretics by after the Council of Ephesus, Nestorians were generally persecuted in and eventually pretty much disappeared from areas held by the (eastern) Roman Empire. However, they were less persecuted than other Christian sects in Zoroastrian Persia, where Christians were generally suspected of being Roman catspaws which these people, who were deemed heretics by the Romans, were less likely to be.

The Nestorians also attempted to proselytize areas north and east of Persia and had some early success among the Turkic people in Modern-day Uzbekistan and Turkmenistan. However, after the Muslim conquest of Persia, they were largely marginalized by the spread of Islam.

The POD would involve a more successful conversion of peoples between the Caspian Sea and the Himalayas, sufficiently so that they are not subsequently converted by the Muslims. Perhaps there is more of a focus on converting the Turkic peoples to try and start up a Nestorian nation and thus less effort spent on trying to convert India and Tibet. Perhaps there are simply some lucky breaks instead. Perhaps Nestorian faith copies some elements of Zoroastrianism (which people living next to Persia would at least be aware of) due to the fairly amicable relationships between the clergies and the fact that Zoroastrian priests becoming Nestorian was not uncommon.

How would this affect the steppe nomads of Central Asia? What would the relationship between the Nestorians and the Byzantines eventually be like?
 
I think it's far more interesting how their relationship with Eastern Slavs would be, they could have OTL relationship, but alternate we could simply end up with a closer relationship something like between Orthodox and Catholic, the result could be that Central Asia was seen as part of Europe, a periaphery psrt in the same manner people saw Russia. But that could also result in the Nestorian Turks imported European farmers and merchants, the same way Eastern Europe imported Western Europeans. This could mean that local Turkish princes married into European royalty.
 
Having islam penetrate with more difficulty in Central Asia would do it. Possible PoDs for this outcome could be:
-Having Persia resist the muslim invasion
-Preventing the Abbasid revolt (the Abbasids focused quite a lot on Persia)
-No Battle Of Talas, or one that leads to a defeat on the muslims' side. Wouldn't necessarily halt the islamization of Central Asia, but could delay it, or diminish its success.
 
If the Battle of Talas is occurring, the Muslims and Chinese are already fighting over who gets to culturally/religiously dominate the Turkic tribes. If instead of the Karluks defecting from the Chinese side, a turkic tribe (which in this timeline is at least partially Nestorian in their beliefs) defects the muslim side, this could be pretty much the last chance for this timeline's request to suceed. Afterwards, the Turkic people could demand greater autonomy in return for some form of tribute or acknowledgement of Chinese suzerainty. Good acess to chinese goods and science would certainly give them a leg up, but being absorbed by China would be detrimental to forming a unique culture.

In any event, I see dominating the (northern branch of the) silk road as one of the primary geopolitical goals of the suggested nation(s), becoming a bridge between the east and the west.
 
Having islam penetrate with more difficulty in Central Asia would do it. Possible PoDs for this outcome could be:
-Having Persia resist the muslim invasion
-Preventing the Abbasid revolt (the Abbasids focused quite a lot on Persia)
-No Battle Of Talas, or one that leads to a defeat on the muslims' side. Wouldn't necessarily halt the islamization of Central Asia, but could delay it, or diminish its success.

That would result in a Central Asia of many faiths, including Tengrism, Buddhism, Zoroastrianism, Iranic polytheism, and even a few Shaivite Hindus left over from the Kushans and Hepthalites. Nestorianism winning out is far from given

I think, for a Nestorian Central Asia, you need a weaker Persia, and thus weaker Magi and less reform of Zoroastrianism. Then, you could have Nestorian Christianity convert more Persians (but still not a majority - that's impossible without outright conquest) and a sufficient base for missionaries to be sent into Central Asia.
 
A central Asia that contains several competing religions, with at least one officially Nestorian nation strong enough to resist being absorbed by any of the surrounding regional powers for more than a few decades, would still fit the purposes of this thread, more or less.
 
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