I was gonna suggest using (DragonLance) Lord Soth's fall from grace as an inspiration, but Myrddin seems to have beaten me to it (even if they weren't thinking of Lord Soth in particular).
The fact that the character has a current responsibility opens up some great roleplaying opportunities...
Is this a known campaign world or one of your own creation? 'Amoria' sounds a bit Tolkien-esque.
With respect to the persecution of wizards - does that mean that it's a low-magic setting. I ran one of those once - certainly made the players a little more cautious in combat, since clerics were...