Fred M. Donner is Professor of Near Eastern History at the University of Chicago. He is the author of three books: The Early Islamic Conquests, Narratives of Islamic Origins, and Muhammad and the Believers.
After summarising the traditional Islamic account of the origins of Islam, Donner gives his own perspective, as laid out in Muhammad and the Believers. He contends that Islam was originally an ecumenical movement of ‘Believers’, Mu’minūn, aligning the many currents of Arabian monotheism into a torrential conquest.
If you’d like to know more about Donner’s approach, by all means read the book: it’s meant for a general audience, and shouldn’t require any specialist knowledge. As an antidote, here’s an especially cutting review from Patricia Crone, which shows up the limits of Donner’s model.