User blog comment:SoDreaxx/Si Gandalf a Maia ?/@comment-25267670-20150610102630

Yes. It was mentioned in The Silmarillion. Gandalf was under the name of Olorin. So this is possibly the reason why your friend did not know this. The order of Wizards, the Maiar who came to Middle-earth after the first millennium of the Third Age. Of these, five came to the northwestern regions; Saruman, Gandalf, Radagast, Alatar and Pallando. References: Unfinished Tales Part Four"The Istari" and somewhere in The Silmarillion.