Fawkes
I have way too many book recs, but the first one that comes to mind is Fawkes by Nadine Brandes. And what's funny is I'm not as big a fan of her other books, but this one left me reeling at how good it was.
It's a historical fantasy (with a little bit of romance) set during the Gunpowder Plot. The main character is the son of Guy Fawkes, and he's caught in the middle of this conflict between Keepers (this world's version of Catholics, basically) and Igniters (Protestants, I guess). He's also suffering from a plague that's turned his eye to stone, and on top of all that, there's someone in his head trying to tell him things that his father says are false.
This is a really really bad description, but I promise, check out the book. It is so good. It's one of the few pieces of Christian fiction that is actually good, I think. I almost hesitate to call it Christian fiction because that just makes me think of badly written books. But, yeah, anyway, check it out.