Isn't the origin of Islam supposed to be in its Judaistic roots as relating to the two soons of Abraham? If I remember correctly, I think the two sons that Abraham had, Ishmael and Isaac, both went on to father respectively the two religions of Islam and Judaism respectively.
Apparently there has been some debate among scholars about the origins of Islam. This is not surprising, since the origins of almost all religions provoke serious discussion among serious scholars. A convenient overview of recent discussions of this matter can be found here:
Islam, in a sense, represents the return to the monotheistic religion of Judaism; it acknowledges the Christian influence and importance and then expands on it, just as Christianity expands on Judaism. However, the specifics change, in some cases drastically, like in a game of "telephone" where the message is altered; one issue is that Islam ignores all the continuing research and commentary of the two prior religions as heretical. If it truly intended to be the culmination of all religion, it would incorporate values from both, instead of (generally) rejecting them.
Islam is regarded as the culmination of the Abrahamic monotheistic faiths. In fact, some Muslims believe that Islam has always existed, but date its official beginning to the Prophet Muhammad's journey from Mecca to Medina. This is dated to 622 C.E. which is the beginning of the Islamic calendar.
Islam originated with the Prophet Muhammad. He lived in Mecca in Saudi Arabia from about 570 to 630 CE. Muslims believe that the Koran was revealed to Muhammad by God over the course of more than 20 years. Muhammad then preached the new faith to the people of Mecca. This was the beginning of Islam.
According to secular history Islam first came into origin during the 7th century, in 610 AD. But according to Muslims it has been present, in one way or another, long before the time of the Prophet Muhammad (PBUH), it can traced back to Adam (AS), and that the name Islam was given to it in the 7th Century.