WI: Catholic Rome under Muslim rule for centuries

To me, the interesting option is that the Arabs DON'T take all of Italy. A Muslim control of Sicily plus the west of the boot up to Rome/Tuscany, a Christian-Lombard/Frank north and a Byzantine eastern boot could easily fit in.
 
That has an interesting impact on world history. Fast forward a few centuries and Muslim explorers discover the Americas. The upshot appears to be that Christianity ends up as a footnote to history, an obscure cult that died out in the early middle ages and isn't missed by anyone.

On the other hand, since Jesus is a Prophet in Islam and Muslims revere him as a messenger of God, plus the fact that the Quran mentions Jesus more times than it mentions Muhammad, and you can see that Jesus' legacy is very much still alive, just in an Islamic form.

Let's not forget that Christianity was the majority faith in large portions of the Islamic empires until the High Middle Ages, and as recently as a century ago it formed a considerably larger share of the population in the Middle East than it does now. During the 20th century, a lower birthrate (due to generally higher socioeconomic status) and a higher rate of emigration (owing to numerous overseas opportunities for Christians) caused its numbers to decline. Those two factors likely wouldn't be the case ITTL. And of course Christianity is also the main religion of Ethiopia. It'd still be a major religion but just not the most widely-practiced one.
 
To me, the interesting option is that the Arabs DON'T take all of Italy. A Muslim control of Sicily plus the west of the boot up to Rome/Tuscany, a Christian-Lombard/Frank north and a Byzantine eastern boot could easily fit in.

Putting your army thru land in Syria and North Africa is one. Transporting your troops while fighting a very powerful Roman navy with Greek fire is another.

Lets assume that the Arabs conserve their resources and energy so rather attacking France and Constantinople, Anatolia they put all their resources towards Italy instead. That seems quite possible from a armchair generals points to focus all your logistics at one specific point. I dont know from their current political standpoint if attacking Italy is more rewarding than attacking France, Anatolia and Constantinople.
 
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