Gandalf-

            Gandalf was the name givin to him by the mortal men of middle earth and was called a wizard or istar in the elven language.. Few if any knew his purpose or origin in Middle Earth say a few kings of great elven lands or the rest of the council of white...

            To explain his origins you must first know about some of Middle Earth and where it comes from..

            Before Middle Earth existed there was only a void in which Iluvatar brought forth the Ainur his creations, amoung them were the Valar (the powers of the earth) and the Maiar the lesser Ainur and servents to the higher gods..

            The most powerful of the Valar was Melkor but he sought for power over his bretheren.. a power which only Iluvatar weilded... he sought for it in the darkness of the void and eventually the darkness consumed him perishing all good in his soul for all eternity. Thus he became the Dark Father creater of all evil conception and darkness.

           Manwe was one of the wisest of all the Vala and best understood Iluvatar's designs and was skilled only slightly less than Melkor in the Music of Ainur.. which is basically the magic of creation of which all the Ainur weild.

           Gandalf and his kind, the maiar were born in the void. He and his kind never had privilage of youth in physical form, instead they always appeared as old men.