1920 — Polish-Soviet War Polish Propaganda Poster 1919Polish Position Outside Warsaw 1920Polish Defense of Warsaw 1920Polish Troops c. 1920Polish Tank Column c. 1920 July 22, 1920 — Even though World War I had ended, fighting in the Berezna region continued after the newly established Poland tried to seize lands east of its borders (in present day Ukraine) under Soviet control. Poland initiated its Kiev Offensive in April 1920. In a counter-offensive, Soviet Russian troops battled through the Berezna area and occupied Brest (Brest-Litovsk) on July 22, 1920 enroute to Warsaw. The Berezna area remained occupied by the Russian army through the end of September 1920, until after the Battle of Kobryn, during which the Russian forces were routed. On March 18, 1921, Poland and Russia signed the Treaty of Riga ending the war, with Russia ceding additional lands to Poland.