I am going to disabuse the notion of a Christian arabia inevitability. Quoting from another thread:-
From what i understand, having done some research on Arabia, the pagan goddesses Al-Uzza, Al-Lat and Manat were becoming increasing overly revered in Arabia, and soon enough they were starting to encompass all the domains of the other minor gods. It seems that much like Judaism, Arabian paganism was dropping the other gods in favor of these three deities, and Muhammad himself is said to have credited the strength of this trinity during the conquests of Arabia. Should Muhammad not arise, then a unified Arabic paganism centered around Al-Uzza, Al-Lat and Manat would probably arise, and dominate Arabia, perhaps barring Judaistic Yemen. With the population boom in Arabia, the people would eventually try to expand out of the interior, and we could have an Arabic pagan Iraq and Syria, and even Egypt, if they are lucky. There have also been rumors that 'Allah' as a god did exist in arabic paganism, however in a much diverse sense. So really while Islam may not explode and become a thing, other religions coming from Arabia may explode alongside the arabic population boom and conquer a good amount of territory, especially after the Rhoman-Iranic exhaustion.
Also about assertions about paganism going out......this is a popular trope not evidenced.
From
Arabia and the Arabs: From the Bronze Age to the Coming of Islam chapter 6,
View attachment 648708
And before someone makes the Christian = more economic power agreement
The economical advantage of Christianity was so great that the Jews of Yemen worked in tandem with the polytheists to throw the Christians out. The southern nabateans found it so useful that they allowed with the interior tribes to push the encroaching Byzantine armies out repeatedly and politely showed the door to almost every Christian missionary group. Christian trade with Arabia diminished in Arabia after the 480s to the point that the merchants of Hejaz and Arabia were turning towards Persia, India and Africa according to the Book of Himyars. All in all not a guarantee and not at all Christian determinism like what many in this thread believe. In fact the book of Himyars mentions that Christian traders and political power in Arabia was minuscule in comparison to the economic power wileded by the iranics Indians and Africans. Again, Christianity is a possibility but it isn't determined not as likely as you make it out to be.
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To answer your question directly without quoting myself from another thread, the Levant remains Judeo-Christian, Yemen remains Jewish majority, whilst the rest of Arabia other than Iran and Iraq remains Polytheistic as the religion started to conslidate itself. Also Christianity never had a hold in Central Asia. It was dominantaly Zoroastrian and Buddhist, and remained so until the 11th century, showing its resilience. Also......
This is a very large stereotype and in conflict with general consensus. Religious Extremism existed in Europe, many times in greater amounts and numbers before the advent of Islam. The Fatimids, Ottomans before the 1800s, and Mamluks were known to be rather liberal empires for their time as well. This is a rather demeaning statement to Islam and all of its adherents, a vast majority of whom are not extremists.