Sharpe's Sword (Bernard Cornwell, 1983) is a page-turner culminating in the Battle of Salamanca in 1812. As I often say in commenting on these books, this isn't a good entry point to the series as a whole--for that you want either Tiger or Rifles, and in general I prefer chronological order to publication order, which IMHO would get whiplashy in a hurry.
There's very little I can say about my reaction to this particular volume without giving away spoilers. Suffice it to say I was taking mental notes about clues and misdirection for my possible mystery project, even though Sword isn't a mystery as such. Also, on the one hand I like Sharpe a lot and even identify with him in a strange way (much like I used to identify with Spike in my Buffy-watching days--when you're under a lot of pressure in real life, including the pressure to behave and be nice, there's something immensely cathartic about some nice fictional ass-kicking). But OTOH, I often want to throw him against the nearest wall and inform him of what an IDIOT he's being, and the urge has never been stronger than in this book.