In 1920, the Polish army stopped the Soviet march to the West defeating the Red Army in the famous Battle of Warsaw which took place over August 13-25. August 15 symbolises this crucial victory and the date is celebrated as the Polish Armed Forces Day.

In the aftermath of WWI, Poland fought to preserve its newly regained independence, lost in the 1795 partitions of Poland. Poland’s leader, Marshal Józef Piłsudski wanted to expand Polish borders to the east and create a new multinational federation, the Intermarium, which would form a counterbalance to German and Soviet imperialism.