1918–1919 conflict between the Second Polish Republic and West Ukrainian People's Republic
The Polish–Ukrainian War, from November 1918 to July 1919, was a conflict between the Second Polish Republic and Ukrainian forces (both the West Ukrainian People's Republic and the Ukrainian People's Republic). The conflict had its roots in ethnic, cultural, and political differences between the Polish and Ukrainian populations living in the region, as Poland and both Ukrainian republics were succ... Wikipedia