The Polish Committee of National Liberation was set up in 1944 by the Communist Poles and Russians at Lublin, and a few days later, was recognised as the temporary Polish government by the USSR.
The Poles had been promised the old lands up to the Oder and Neisse rivers, occupied by Germany, in return for the eastern part of Poland. This promise was never made formal, nor was it completely accepted by the western Allies. In May 1945, at the end of the war, the Provisional government occupied these western territories. The Polish population of the old eastern provinces, including Lwow, moved west as their territories were absorbed by the USSR; the German population was largely removed to the German Democratic Republic (later to become known as East Germany). This new Poland corresponded very closely to the Poland of 1138, and now contained very few of the minorities (such as the Lithuanians, Ruthenes and Jews) which had given the Commonwealth such variety.
In the January elections of 1947 the main non communist politicians were defeated (by use of fraud and violence) and emigrated. Wladyslaw Gomulka, leader of the Polish Worker's Party (Communist), became undisputed leader of Poland, then, in September 1948, Gomulka was dismissed. An era of full Stalinist dictatorship and headlong industrialisation began under the leadership of Boleslaw Bierut. In December the Polish Worker's Party and the Polish Socialist Party fused into the Polish United Worker's Party.
After discovering that they had been cheated of some of their wages, 15000 workers of the Cegielski and Stalin works demonstrated in 1956, and, when attacked, rioted. These were the Poznan riots which lead to "The Polish October" when Stalinism was overthrown. Gomulka managed to persuade Khrushchev, the Soviet Premier, that he could control the situation, and so Soviet troops which were on stand by were not used (unlike in Hungary where the situation led to bloodshed in the Hungarian Uprising). Gomulka returned to power and a new, more independent relationship with the USSR was established.
With the political thaw, in 1968 the universities became centres for discussion and learning again. The Israeli victory over the Soviet backed Arabs in 1967 was greeted with glee; "Our Jews have given the Soviet Arabs a drumming!" Anti Russian feelings grew until, when the authorities banned a production of Mickiewicz's anti Russian "Forefathers' Eve" in January, student riots broke out in Warsaw and Krakow. These were forcibly put down and a period of repression against Intellectuals and Jews ensued. Gomulka found himself under pressure from the repressive Nationalist "Partisan" faction, led by Mieczyslaw Moczar, and reluctantly had to "encourage" the Jews to emigrate (his own wife was Jewish). He got Soviet backing by letting Polish armed forces take part in the Warsaw Pact repression of the Czechoslovak attempt to create a more liberal situation.
A sudden increase in the price of food in December 1970 led to riots in the Baltic cities; Gdansk, Gdynia and Szczecin, which were repressed with great bloodshed. The fighting spread and led to the replacement of Gomulka by Edward Gierek, who managed to calm down the situation by preventing the price rises and promising reforms. A policy of rapid industrialisation, based on Western imports and credits (a policy which was to bankrupt Poland), and an artificial rising of living standards began.
To ease the foreign debt, by 1976 Gierek had to take steps. He increased, amongst others, the price of "luxury" consumer goods, and in June, a 60% increase in food prices. Violent strikes in Warsaw and Radom led to a cancellation of the price increases, but also led to repression by the Citizens' Militia (ZOMO) and severe sentences. Opposition groups were set up, like KOR (Committee for the Defence of the Workers). The economy "overheated" and led to a period of acute consumer shortages, especially meat, and a soaring foreign debt.
In October 1978, Karol Wojtyla, Cardinal of Krakow, was elected Pope. The Polish sense of "destiny" began to surface. In June, 1979, Pope John Paul II visited Poland at a time when the economic crisis was deepening.
Fresh price rises in July 1980 touched off nation wide strikes. In August they reached the Lenin Shipyard, Gdansk, where Lech Walesa became leader. At the end of August the Gdansk Agreement created Solidarity as an independent, self managing trade union.
On December 13, 1981, General Jaruzelski, prime minister, minister of defence and first secretary of PZPR, declared a state of martial law and suspended Solidarity. Gradually, as the country's political and economic life returned to normal, martial law was lifted (July 1983). From 1986 onwards, there was great discussion as to the way the country could develop which led, in 1988, to a referendum and fresh elections which opened the way to the massive changes of 1989 and the return of Democracy.
In December 1990, Lech Walesa was sworn in as the first non Communist Polish President since WW2.