There is no evidence that Mecca existed, nor Muhammad, although the latter is debated. The Birmingham codices have been judged to have been written before the time of Muhammad, which is likely as the two segments carry a story normally associated with Egyptian religion.
My take is that, in parts, it is a book of conquest.
There is no clear evidence of Christ. Certainly not one hair of evidence for Moses. For me, the real story of the development of monotheistic is far more interesting as it concerns the development of human thought.