History of Poland
The Polish People's Republic ("Polska Rzeczpospolita Ludowa") was established under the rule of the communist Polish United Workers' Party (PZPR). The name change from the Polish Republic was not officially adopted, however, until the proclamation of the Constitution of the Polish People's Republic in 1952.
Second Polish Republic
The Second Polish Republic, commonly known as interwar Poland, refers to the country of Poland in the period between the First and Second World Wars (1918–1939). Officially known as the Republic of Poland (), sometimes Commonwealth of Poland, the Polish state was re-established in 1918, in the aftermath of World War I. When, after several regional conflicts, the borders of the state were fixed in 1922, Poland's neighbours were Czechoslovakia, Germany, the Free City of Danzig, Lithuania, Latvia, Romania and the Soviet Union. It had access to the Baltic Sea via a short strip of coastline either side of the city of Gdynia. Between March and August 1939, Poland also shared a border with the then-Hungarian governorate of Subcarpathia. The Second Republic ceased to exist in 1939, when Poland was invaded by Nazi Germany, the Soviet Union and the Slovak Republic, marking the beginning of European theatre of World War II.