One of the great challenges in writing this sort of book is to make the dry research come alive. Exposition is a no-no, especially if it doesn’t serve the story. While it’s very nice to have a lot of detail, if it’s extraneous it will kill the momentum faster than just about anything. One of the great techniques I came across was to read the first-person accounts of various scenarios and then spend some time imagining what it would have been like. How would I describe the situation? What did I see? Was I cold? Hungry?
Another thing that helped this story in particular was the use of first-person throughout. I realized the strength of this point of view while reading John D. MacDonald. It adds to the immediacy. The disadvantage is that it is difficult to describe the protagonist in any substantial way, though that might be a strength. My protagonist is a reticent guy, so most of the sense the reader gets of him comes from the reaction of other characters. I haven’t read much first-person historical work, though it is common in detective fiction. Audie Murphy’s excellent To Hell and Back was not only first-person, but present tense. More on that later.
Here’s a clip of Bob Hope and Frances Langford performing at Polebrook. This scene is depicted in the novel.