Box Office Mojo at this time estimates that it has made approximately 9 Million since its release, a bit more than half in the US. I'm not certain (nor is the site) what its budget was, but it's safe to assume it was on the lower end of film budgets, being more a period piece than a summer blockbuster. My guess is that it'll do pretty well in the video market as well.
Hopefully we'll see some more movies of similar stripe soon. I for one would really enjoy a movie retelling of the struggle of Poland against the Soviet Union from 1919-1921
Between WWI and WWII really is the black hole (or perhaps memory hole) of history for most of us in the US, with the very minor and very partial exception of the Spanish Civil War.