Rules of Ascension by David B Coe
"For 900 years, since the Qirsi War, the Forelands have enjoyed relative peace. The Qirsi leaders, Weavers whose powerful magic could bend to their will not only the elements but also the thoughts of others, were all killed. The rest of the pale-skinned Qirsi were scattered throughout the realm. They were no longer a threat without their multi-talented leaders.
But though most Qirsi live normal lives, and some even serve lords as advisors, all is not well in the realm. There is a Weaver in the Forelands again, secretly sowing seeds of rebellion against the physically hardier but unmagical Eandi.
Lord Tavis of Curgh, raised to succeed his father as duke, and engaged to the beautiful Lady Brienne of Kentigern, seems bound for greatness. But just as his life seems complete, he is accused of a horrific act. Little can Tavis know that the Weaver is using him as a pawn in a vast plot.
Now, only a Qirsi gleaner can help Tavis survive his doom, reclaim his good name, and prevent a devastating civil war in the Forelands."
Mass market, a nice copy!