The book itself the author claims is a biography, or a multi-biography work. Granted based upon historical events, yet to many (including many of those working on the film) kept considering it a novel by many standards. Many times while working on set filming various things someone would mutter "when did this happen, I dont remember this ever occuring". Common response "Its just a novel, get over it".

Basicly how many created and fabricated events can one place into a historical based work and it still be classified and considered entirely non-fiction. It wasnt entirely fabricated but many parts thereof certainly were. Common habits to "fill-in" gaps in the story line with various fodder to better help charactor development. Known historical events and situations existed but most that didnt fit the given agenda were left on the side. Hense ones personal opinion and agendas be placed into it implied to be historical fact, when it frequently isnt. Typical habits of many modern historical writers, implant their personal ideal version v/s what history may record as being different.

Interestingly "Killer Angels" (basis for Gettysburg Movie) was indeed considered a novel. Also based upon historical events and real charactors, but similar fill-ins of sketchy or fabricated events to fill in blanks and charactor development in the story line in simular fashion... Is something to be a true non-fiction Biography if large parts of known recorded historical events are purposely left out because it could paint a different or conflicting picture of a given situation than the modern author only wants people to see.

Just an observation
Frederick