L E Modesitt Jr - Corean Chronicles

"Millennia ago, a magical disaster caused the fall of a great civilization that spanned a continent, and ended a golden age. Corus today is a world of contending countries, of struggling humans, strange animals and elusive supernatural creatures. Though much has been forgotten, it is still a place of magical powers, and of a few people who are Talented enough to use them.

Even as a child, Alucius showed very strong Talent. He was warned never to reveal it, lest others seek to exploit it. But as he grows to young manhood, Alucius must serve in the Militia like his father before him. When his country is invaded by the slave armies of the Matrial, immortal ruler of a nearby land, Alucius is captured and magically enslaved.

A time of changes has come upon all of the world of Corus. If the evil surrounding the Matrial is not ended, those changes will not be happy ones. Alucius and his Talent have a central role to play. "

Uploaded per request, will be reading these myself now too I think :)