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.
Provisional Government of the Republic of Poland
The Provisional Government of the Republic of Poland (Polish: "Rząd Tymczasowy Rzeczypospolitej Polskiej" or RTRP) was created by the State National Council ("Krajowa Rada Narodowa") on the night of 31 December 1944.