Should readers feel sorry for an antagonist?
I'm currently writing a story and have an idea for the antagonist's backstory, but it's quite tragic, which might make the reader feel sympathy for him. However, I'm not sure if that might undermine the antagonist's authenticity.
That’s what makes him authentic. If the reader suffers, he can even better understand the motives and even perhaps comes into doubt to really stand on the right side.
Imo doesn’t. On the contrary. Every person has reasons for how he behaves and what he does – also those we consider to be bad/bad. In fact, bad people should also think that they do the right thing – just from their own perspective. Perhaps they are aware that their actions are not accepted by the rest of society, but they still do “the right thing”. Otherwise they wouldn’t do it…
If these motifs are also worked out by the antagonist, this gives the character depth. The question is whether, or how you can manage to convey to the reader the “moral” of your history – so why the antagonist is actually wrong, in his assumption to do the right thing from his point of view.
The more human you do it, the better. The reader should be able to enter him as well as into the hero. If the guy’s just stupid, you didn’t write a good book.