I have a few questions which directly correlate and would like the experts on early Islam to help with some input...
1. Being unsure of the average Arab life expectancy at the time of Muhammad's death I am curious as to how much longer the Prophet could have lived. If he had lived the maximum amount of time possible what more could be expected of his life, teachings, and conquests? And...
2. Who would succeed him had he specifically named a Caliph? The effects of Muhammad clearly identifying a successor are large enough, but who was he most likely to pick as his successor and regent to...
3. ...his newborn son Ibrahim had he lived. Obviously no matter how much more time on earth we give the Prophet Muhammad, we could probably not keep him around long enough to have seen his son Ibrahim ibn Muhammad come of age had the child survived infancy. However, if he had lived in good health and Muhammad had survived long enough to appoint him Caliph in waiting under a Caliph Regent successor (who would then adopt Ibrahim upon the Prophet's death), what would the future hold for the boy? A male heir to Muhammad (and legal heir to Muhammad's successor) holds enough butterflies as is, but Ibrahim was also the half Egyptian son of a Coptic Christian concubine to the Prophet, and despite being a Muslim himself, would no doubt have a unique perspective on the relationship between Islam and Christianity.
And if you don't mind a quick bonus question:
4. Muhammad wrote many letters over the course of his life to Middle Eastern leaders entreating them to convert - and many did. What if he had lived to have been even more prolific, softening the perception of Arabs in the eyes of ERE nobility, and even convincing lesser nobles and rulers in the southern ERE to convert?
With an organized and less actively "anti-non Arab" leadership going into the ATL Islamic expansion possible with the questions I've asked above; could an Arab-Byzantine Alliance be formed against Persia and other threats, leading to a peaceful (if bufferless) or "cold war-esque" border between the Muslims and the Eastern Roman Empire allowing for unhindered Arab expansion Westward?
In such a scenario might it be likely that a growing Muslim trend in the population and under-leadership of Byzantium might weaken Eastern Rome against an internal Muslim coup to Islamize Rome, an external cessation of peace between Rome and its nominal Arab allies, or (most interestingly) both?
Thank you all sincerely in advance.