The Polish People's Republic was a country that existed from 1947 to 1989 in East-Central Europe, and the predecessor to the modern democratic Republic of Poland. With a population of approximately 37,9 million inhabitants near the end of its existence, it was the most populous state of the Eastern Bloc after the Soviet Union. Having a Unitary Marxist–Leninist communist government, it was also one of the main signatories of the Warsaw Pact. The official capital since 1947 and largest city was Warsaw, followed by industrial Lodz and cultural Kraków.
The former country covers the history of contemporary Poland between 1952 and 1989 under the Soviet-backed communist government established after the Red Army's release of its territory from German occupation in World War II. The name People's Republic was introduced and defined by the Constitution of 1952 which was based on the 1936 Soviet Constitution. The state's name was the Republic of Poland between 1947 and 1952 in accordance with the temporary Constitution of 1947. From 1952 the Sejm exercised no real power, and Poland was regarded as a puppet entity set up and controlled by the Soviet Union.