This is a prequel book to The Priory of the Orange Tree, which I read a few years ago and enjoyed. A Day of Fallen Night takes you back to earlier days of The Priory, and we get to see how the blood of the Priory with it’s magic is brought into a kingdom that views magic as heresy.
This is a long book with lots of character and lots of dragons. It’s going to take some work to keep it all straight in your head, but the payoff of a good read is worth it.