I think this book really demonstrates how Ms Nagle has grown into her writing abilities. The first book was well researched and there were several strong characters but the plot seemed to be pretty basic and even predictable. She even included what I would consider to be an amateurish plot device that interrupted the climax of the story. But as she progressed through this series she just got better and better. The research was still outstanding, exhaustive even, but her characters were better written. The plots take place against historical realities so that, of course, can't be changed. But how her fictional characters act and interact with others has become delightful. This last book in the series illustrates that very well, with her long-time character, confederate officer Jamie Russell, becoming truly multi-dimensional. His interaction with Mrs Hawkland, forms the basis for the novel.
Ms Nagle's wartime action scenes are very well done as well. I felt like I was there, not in any kind of heroic battle sense but definitely feeling the fear, the exhaustion, and the filth of battle. Jamie leads his gun battery and is in the thick of battles...you can just hear the explosions and see the men around him struggle to do their duty. The Red River itself, a tributary to the Mississippi River, takes on a life of its own, especially as the Union boats try to free their ships from shallow waters in order to secure the entire Mississippi, a crutial strategy for the war.
All in all, this wraps up a very good historical fiction series. I was happy to see it progress but I wish there were one more novel to finish out the war. This one does take us up to where the end is in sight though, so perhaps another would be anti-climactic. I'm not sure if Ms Nagle planned for another but it seems she has turned her hand to romantic fantasy for the moment.
Next up: I've already begun the third book in the first "Kushiel" trilogy: Kushiel's Avatar by Jacqueline Carey. As we get closer to the end of the year I always try to finish up any series that I have open. That is, excepting those series that I actually plan to read over many years, like "Repairman Jack" for instance.