The Polish Catholic Church suffered enormous losses during the Nazi occupation of Poland in World War II. Its leadership was scattered or exterminated, its schools were closed, and its property was destroyed. Ironically, in the war years this destruction fostered the church's conversion from an aloof hierarchy with feudal overtones to a flexible, socially active institution capable of dealing with the adversity of the postwar years. In the first two postwar years, the church enjoyed considerable autonomy. In 1947, however, consolidation of the East European nations under the hegemony of the Stalinist Soviet Union led to the closing of Polish seminaries and confiscation of church property in the name of the state. The state abolished the concordat and assumed legal supremacy over all religious organizations in 1948.

In the decades that followed, the church adapted to the new constraints, pragmatically reaching compromise agreements with the state and avoiding open confrontation over most issues. Between 1948 and 1981, the church was led by Cardinal Stefan Wyszynski, an expert on Catholic social doctrine whose commanding personality augmented the power of the church hierarchy as a direct conduit from the Vatican to the people of Poland. As a general policy in the early communist decades, Wyszynski avoided fruitless direct campaigning against communist oppression. Instead, he stressed the church's role as advocate of Christian morality. Nevertheless, the cardinal's criticism of PZPR party leader Boleslaw Bierut earned Wyszynski three years under house arrest (1953-56), as well as international stature as a spokesman against communism. During this period, a total of 1,000 priests and eight bishops were imprisoned, and convents were raided by the police in the communist drive to destroy completely the authority of the church in Polish society.

Wyszynski was released in 1956 as a result of severe social unrest that forced a change in party leadership. The release was followed by a church-state agreement significantly relaxing restrictions in such areas as religious teaching and jurisdiction over church property. This agreement marked a general softening of state religious policy at the end of the period of hard-line Stalinism. Ten years later, the church's lavish celebration of the millennium of Polish Christianity strengthened the identification of Polish national consciousness with the church and, in the process, the state's respect for the church as representative of national opinion.

Data as of October 1992