The Towers of the Sunset (Saga of Recluce, Book 2)

Rather than accepting a marriage arranged by his mother, the powerful military matriarch of Westwind, Creslin chooses exile, setting out to find his own identity and developing his magical talents through conflict with the enigmatic white wizards of Candar. What Creslin doesn't know he stands in the way of their plot to subjugate the world.