AH Challenge-Revive both the Mongol Khanate and Byzantine empire

AH Challenge is as the title states for any willing to think of a way.
Obviously, neither can be restored to their maximum degree without serious ASB intervention but I think the 20th Century could see watered down versions of both.

In terms of Byzantine empire though it seems that the best bet is the Greco-Turkish war with either Ataturk being killed off or the Bolshevik's deciding not to send Gold or armaments to the Kemalists or both. In addition, a better Greek strategy early on would help such as not going crazy and chasing the Turks deep into Anatolia. Instead, maybe they could sweep up the land around the Aegean where Greeks lived and then work out an arrangement with the Entente for civil administration of the straits and Constantinople. That would leave a pseudo-Byzantium even if it is never given the that title officially.

In regards to the Khanate, Roman Von Ungern Sternberg between 1919-1921 during his brief control of parts of Mongolia worked with the Bogd Khan. Ungern wanted to restore the Mongol Empire. However, he was very much outclassed by the Red forces eventually sent against him. Thus, the only way, Ungern gets a revived Khanate is if White forces do much better in general in Siberia to the point where they effectively gain independence and also decide to leave Mongolia to Ungern's continued de facto rule. Alternatively, Japan decides to prop up his regime in Mongolia as a buffer against the Soviets and acts as protector. Either option seems unlikely though.
 
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