Dies the Fire, a Novel of the Change, by S.M. Stirling
Despite Stirling’s workmanlike prose, he is an excellent storyteller, artfully combining science fiction and fantasy into a unique post-apocalyptic miasma. The story is engrossing, realistic (despite its huge early-story Deus ex Machina moment) and totally enjoyable.
Expecting nothing but a diversion on a road trip, I finished it and then bought two of the sequels. If you are a fan of post-apocalypse fiction, fantasy, or alternative history, Dies the Fire will be a delight.
As a side note, reading this book while I was traveling in the Pacifc Northwest brought the story even more vividly to life. Nothing like “Reading in the Setting,” a habit I picked up after reading James Clavell’s Tai-Pan on my first trip to Hong Kong in 1985.