Luin the Sapphire (Aglaril Cycle, 5) [Feitelberg, Rich]

Evan Pierce, priest of St. Michael, and now Baron of Pennarth, must fight a group of necromancers, who have taken over the barony. With him are only a few friends from his religious order. Together, they must reestablish the castle guard, repair the castle defenses, and rebuild the nearby town of Irenrhod, if they have any hope of succeeding. But the dark mages, using the local guild of thieves, intimidate any who questions their authority. More stubborn people are visited by the mindless, animated servants of the wizards, dead corpses from the grave that can rend stone and flesh, and spread terror into the hearts and minds of everyone. How his opponents got so powerful that they can create a horde of zombies is a mystery to Evan. The Michaeline priest must discover the power source of the dark wizards and defeat them before the zombies destroy Pennarth and everyone in town is murdered.