One of the main scenes in the movie is the psychotic attack of the Kappel supporters. However this event never happened as the groups of Chapayeve and Kappel never met real life as the opponents of Kappel was the 24th division, not Chapayev's 25th division.
The uniforms of the White fighters in the movie were actually worn by the 1st Officer General Markov Regiment of the Voluntary Army.The fighters against Chapayev had different uniforms.
In the movie Chapayev is riding a horse. However it could not be possible since Chapayev got a wound during WW1 and couldn't actually ride a horse. Furthermore as a commander of a shooting division he preferred riding a car.