A knight wakes on a hill surrounded by the detritus of battle. He walks to a nearby city, where he finds employment selling 'hands of glory' in the market. A horribly scarred and mad princess meets him there. Eventually they are married and he must go on a quest to cure her.
He meets the dog-person who maimed her, is turned into a stag, and at the conclusion of the book is sent back to his own time and place, a battle in Scotland where he is fighting his greatest enemy.
I believe it was a trilogy of novels. These are just the points that stand out vividly that I can be sure were from the same series- I read the books about 6 or 7 years ago (2007-2008) so it's all quite blurred