AHChallenge: Muslim Americas, Christian (or other religions) Middle East

How can we have an at least 50% of the population of the American continent are muslims, while the Mideast is dominated by other religions.

Thanks in advance!
 
Christian middle east: depending on your definition of the Middle East, the easiest way I can see is that the Second and Third Crusades stick and Christendom retains control of Jerusalem and surrounding areas long enough to convert the Islamic population. It does help to bear in mind though that there was always a Christian minority in most parts of the Middle East and continues to be one to this day.

Islamic Americas: First thing that comes to mind is Martel loses at Poitiers in 732. Islamic expansion takes the Frankish kingdoms and possibly goes into Britain and Germania and sticks. Fast forward to the 15th century and you've got Muslims doing the colonization.

As for how you can get both in the same TL, that's a bit tricky. Christianizing the Middle East presupposes that the Christians have a base to operate from, which throws out the Islamic Europe necessary (IMO at least) to create an Islamic America. The minority Christian groups indigenous to the area lack the military or political ability to affect a sustained religious revolt against the caliphs or later the Ottomans, although if you're lucky you *might* get a series of tolerant Sultans who let Christianity flourish in Jerusalem et. al.
 
Islam becomes the largest religion in China, which goes on to colonize the Americas. Maybe Islam's initial expansion is blocked by the Byzantines so most of it's expansion is focused east?
 
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