Franco-Mongolian Alliance

It could have worked. There were many Nestorian Christians in the Il-khanate who would have supported the alliance. The attack of the Mongols could have led to a survival of the crusader states, and a Mongol state in Persia.
 
this would make sence, there were such plans, the catholic church was supposed to send delegations to the Khan and Venice also considered diplomatic relations, all aimed at some kind of alliance against the Arabs, in the context of the crusades, but most of it failed due to lack of European interest, although one of the popes did send two priests, to represent the church in a sort of pan-imperial religious convention, but that didnt do much

Marco Polo had a lot to do with some of it, being on a sort of trade/diplomatic mission for the Mongols
 
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