I was sent this film (with subtitles) on DVD by a friend in Poland and found it engrossing.
I guess it helped that I had already read a book on the subject, Warsaw 1920 by Adam Zamoyski, so knew what direction the film was going before it started, and that helped my understanding. The love interest and sub-plots enhanced the film, but again some knowledge of 20th Century Eastern European culture and politics helped.
My initial thoughts were that some of the colours were rather vivid and maybe unrealistic but a variety of cinematic styles were used and as they were not used frivolously they worked well in the end. The cabaret scenes showed glamour, style and sensitivity where necessary - all in stark contrast to some, frankly, barbaric and unglamorous battle scenes. I suspect that they were actually quite realistic representations of the fighting. There were some interesting touches that most people would not think about eg the taking of soldiers'/prisoners' boots (sometimes before their wearers were dead) because of their value at the time.
The principal story is true and the outcome of the battle ultimately decided whether Poland enjoyed independence between its partitioning until the end of WW1 and its invasion by the Germans and then the Russians in 1939.
For those with an interest in Eastern European history, it has been said that Stalin's treatment of the Polish Army officers in WW2 (see the superb film Katyn) was determined by the outcome of this battle.
