Factual error: Prime Minister Peter Stolypin is shown at the Romanov Tercentery, which marked 300 years of Romanov rule. Stolypin died in 1911, yet the Tercentenary was held in 1913. Also, Alexei's Spala incident happened in 1912, and was also shown after the Tercentenary.
Deliberate mistake: While on the sideline during a game, Sayers tells Piccolo that he should ask Dr. Fox to give him something for his hay fever, and Piccolo heads back to the field. The next close up of Sayers is a flipped shot; note the "40" on his jersey. (00:41:55)
Other mistake: At the very beginning of the film, we see Christie commit a murder at the end of the Second World War whilst wearing the uniform of a Special Constable. Christie served during the First World War, and he wears the ribbons of the 1914 or 1914/15 Star, the British War Medal and the Victory Medal on his tunic. Unfortunately, whoever put them on put the bar upside down - they read from left to right VM, BWM, Star.