This movie is to what happened at Sarajevo what Stone's JFK was to what happened in Dallas.
The assassination of Franz Ferdinand was not a German/Austrian plot but a Serbian one of which some Russian officials, at least, were aware.
The script is fascinating and so is the story, and I do recommend it, but the film is not flawless, even apart from its dramatizing a conspiracy theory.
I am thinking of the total silence and relative immobility of the crowds at the scenes of both the first (a bomb) and second (a pistol) attacks, and at the hospital gates.
We have all seen actual video of crowds at scenes of attacks, and they are not remotely silent and far from immobile.