[Kolokotronis]

"Part of Islam was derived from Gnosticism, but much of it is derived from ancient Arab religious beliefs."

And from the influence of Nestorian monks on Mohammed. There were also various strains of Marian heresies, including on in which she was worshipped as a goddess which worked their way into Mahammedanism. Nestorianism still exists in pockets here and there from Syria to China. Most of its influence elsewhere is seen in certain Protestant views of the nature of Christ. Of course Judaism had a major influence, especially on the nature of the mohammedan god allah.

[GoLightly]

You're right about the Nestorian influence & I think there's also some Zoasterism thrown in for good measure.

Of course Judaism had a major influence, especially on the nature of the mohammedan god allah.

They pulled the founder of their religion from Judaism, the whole Abraham thing. They are the children of Ishmael, the older son born to Abraham. Ishmael was the son Abraham offered in sacrifice & his inheritance was usurped. The Jewish prophecies about the Messiah are meant for them.