First was a novella from The Expanse universe by James S. A. Corey, Gods of Risk; pretty solid. Unfortunately, I read it out of order, so I gather I'm looking at characters that I didn't meet in the first book that I recently finished. I'm still enjoying this universe that Corey (two writers, actually) has invented.
Then, Osprey Campaign #31: Yarmuk 636AD: The Muslim Conquest of Syria which is loaded with maps to set up the battle which broke the back of the Byzantine Empire. Not bad.