There is zero evidence Mohammed existed, no contemporary accounts of any kind as to the events recorded of this cartoon character's "biography," zero - zip - nada - not until seventy years after the date of his supposed death.
Meanwhile we have more historic evidence of Jesus Christ than there is of Julius Caesar.
Islam is an Arab mass movement, a political cause with religion added as an afterthought, stolen and stitched from contemporary Christian and Judean orthodoxies.