The Polish -- Soviet War ( February 1919 -- March 1921 ) was an armed conflict that pitted Soviet Russia and Soviet Ukraine against the Second Polish Republic and the Ukrainian People 's Republic over the control of an area equivalent to today 's Ukraine and parts of modern-day Belarus .
The Polish -- Soviet War ( February 1919 -- March 1921 ) was an armed conflict between Soviet Russia and Soviet Ukraine against the Second Polish Republic and the Ukrainian People 's Republic . It was for control of what is present day Ukraine and parts of present day Belarus .