[10] In 1937, Pius XI rejected atheistic communism in an encyclical entitled Divini Redemptoris as "a system full of errors and sophisms", with a "pseudo-ideal of justice, equality, and fraternity" and "a certain false mysticism",[10] and contrasted it with a humane society (civitas humana).
After the Italian parliamentary election of April 1948, in which the communist-socialist coalition won 31% of the vote, the Holy Office began to study the issue of communism in order to give guidance to Catholic lay people and clergy with questions about support for communist parties.
[11] An additional impulse for Vatican action against communism arose in Czechoslovakia, where the communist government, installed by a coup d'état in February 1948, undertook a campaign to take control of the Catholic Church by several means.
Among other measures, it created an organization of priests favorable to the regime, took control of church finances, and demanded that pastoral letters to the faithful or the clergy be approved by government ministries.
[13] The document, however, did not mention the Italian Communist Party, which had changed its statutes in 1946, removing an explicit profession of Marxism-Leninism, and opening to participation by citizens, "independent of race, religious faith or philosophical convictions".
[10] In the spring of 1949, pressure on the Church in Czechoslovakia was increasing, and, according to Cardinal Giovanni Battista Montini, then papal Secretary of State, Pope Pius XII, had come to feel that there would be no effective diplomatic opposition from the West.
[11] The document, as published in the Acta Apostolicae Sedis, bears the date July 1, 1949 and the heading Decretum (Decree), and is presented in the form of a dubium: that is, in question-and-answer format.
The socialist governments of the Eastern Bloc founded associations of priests that either supported communism or were willing to cooperate with the state; clergy belonging to such organizations received favours by being appointed to administrative positions.
In 1950, the archbishop of Warsaw Stefan Wyszyński was able to reach an agreement with the Polish socialist government - in exchange for the passive support of the Polish Catholic Church for communist rule and policies, the state would permit religious classes in schools, maintain theology faculties in state universities, maintain chaplains in the army and preserve the independence of Catholic universities and religious orders.
An anti-communist cardinal August Hlond, considered the "most loyal of prelates", admitted that he "supported what would become the Polish hierarchy’s policy by suggesting that the Vatican should have played a more subtle game with the new Communist regime".
[24] While some have argued that such Decree has been tacitly abrogated by the implementation of the Second Council of the Vatican,[25] this has never been confirmed by the Holy See and the pastoral constitution Gaudium et spes has explicitly condemned materialistic and atheistic ideologies.