You might want to have something in the cover that the book is "A dramatization of real events." This way it lets people know that while the crux of the story actually happened, historical events were changed for narrative purposes. For example, because the real events and conversations were so well documented, the film "Apollo 13" wich depicts the events surrounding the aborted moon landing of the same name, some elements in the film were dramatized for audience's effect. For example, the three Astronauts never had any fight between them over who caused the problem in the first place (in real life, they were all proffessional pilots and aviators and knew that whatever they felt, it was best not to have shouting matches until their feet were firmly on terra firma.). Another scene, where an engineer dumps all the items the astronauts have on board to solve the literal "square peg into a round hole" was fabricated for audiences convience and to illustrate why the feat of engineering was amazing. While it was true that NASA engineers had to solve the problem of replacing the Lunar Modual's (LEM) round CO2 scrubbers with the Command Service Module's (CSM) square CO2 scrubbers was an actual problem, the engineer laying out the potential componants and telling his men they had to figure this out never happened. In real life, the engineer depicted in the scene was told the problem at his Houston area home and told to come in to help solve it. He had the solution worked out in his head by the time he rolled into the parking spot (the reason the issue happened was the two vehicles were made by two seperate contractors, LEM by Grummin and CSM by North American Aerospace, and the carbon scrubbers were not required to be compatable.). And most dramatically of all, Flight Director Gene Kranz never said "Failure is not an option." The closest any Apollo 13 mission controll personel got to saying this was FDO Flight Controller Jerry Bostick, who said upon reflection of the real incident... during a research interview he gave with the Apollo 13 writers during script drafting. He was asked "Weren't there times when everybody, or at least a few people, just panicked?" and responded with the following quote:
"No, when bad things happened, we just calmly laid out all the options, and failure was not one of them."
At the time he gave an interview he felt that this response lead film writer Bill Broyles to become bored with the interview and was shocked to find out that upon returning to their car, Broyles was happily shouting "That's it! That's the tag line for the whole movie, Failure is not an option."
The line was given to the film's Kranz because it was something he would have said if he had thought about it and summed up the flight crew's whole feeling (It didn't need to be said because, as Bostick had explained in his interview, it was how the Mission controll team was operating in default. There was never a panicked meeting of engineers Kranz had to deliver a rousing speech too because they never panicked!).
A similar famously attributed quote to a Historical person that was never actually said was Admiral Yamamoto's final line in "Torah! Torah! Torah!" where he explained why he wasn't celebrating the sucessful bombing of Pearl Harbor: "I fear all we have done is to awaken a sleeping giant and fill him with a terrible resolve."
Though no record exists of him ever saying this, it was well documented that the line summed up his feeling on the attacks. Yamamoto had studied in America and was well aware of the attitudes of the American people. He was opposed to delcaring war on the U.S. and the manner by which they would open hostilities because he felt his superiors didn't understand Americans. The Japanese wanted to remove opposition to their colonial ambitions in the Pacific and felt if the U.S. Pacific Fleet was crippled, they would sue for peace and quickly end the war (this had actually worked against Russia during the Russo-Japanese War 35 years prior). Yamamoto tried to explain the Americans would not take the attacks lying down and had a strong industrial base that had not been touched by war efforts. They were too strong to fight, but weren't going to start anything with Japan unless Japan started it first, the very definition of the phrase "Waking a sleeping giant."