In 1271, only three years after the fall of Antioch, Nestorian monk turned diplomat Rabban Bar Sauma traveled throughout the Christian world in order to create a Franco-Mongol Alliance, and secure Syria and the Holy Land. In OTL, this didn't work as the crusader noblemen weren't longer united in a Crusades.
But what if Bar Sauma was paid heed, and a new Crusade was called?
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