Deryni Rising (Chronicles of the Deryni Series #1)

In the kingdom of Gwynedd, the mysterious forces of magic and the superior power of the Church combine to challenge the rule of young Kelson. Now the fate of the Deryni -- a quasi-mortal race of sorcerers -- and, indeed, the fate of all the Eleven Kingdoms, rests on Kelson's ability to quash the rebellion by any means necessary . . . including the proscribed use of magic!