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.
Polish People's Republic
The PZPR was finally disbanded on January 30, 1990, even if Wałęsa could be elected as President only eleven months after. The Warsaw Pact was soon followed on 1 July 1991 and the Soviet Union ceased to exist in December 1991. On 27 October 1991, the first entirely free Polish parliamentary elections since the 1920s took place. This completed Poland's transition from a communist party rule to a Western-style liberal democratic political system. The last post-Soviet troops left Poland on 18 September 1993. After ten years of democratic consolidation, Poland joined OECD in 1996, NATO in 1999 and the European Union in 2004.