Orientales omnes Ecclesias

Orientales omnes Ecclesiae (December 23, 1945) is an encyclical of Pope Pius XII to the faithful of the Ukrainian Greek Catholic Church. It commemorates the three hundred and fiftieth anniversary of the Union of Brest.

In his encyclical, Pope Pius XII explains that many trials and persecutions took place in the last three hundred and fifty years, but that the Ukrainian Greek Catholic Church always came out strong. He reminds of the many favours and assistances the Church received from Rome and how his papal predecessors always supported the independent culture and rite of the Oriental Church. In the last part of the encyclical, he addresses the grievances facing the Ukrainians in 1945. Aware of the persecution of the faithful and expects even more:

While most Oriental Christians belong to an Orthodox Church, some like the Ukrainian Greek Catholic Church and the Ruthenian Greek Catholic Church Church, are united with Rome, which allowed them to keep their own Oriental liturgy and Church laws. The Ruthenian Catholic Church is located in Ukraine. Ruthenian Catholics call themselves Rusyns. They are closely related to the Ukrainians and speak a dialect of the same language. The traditional Rusyn homeland extends into northeast Slovakia and the Lemko region of southeast Poland. Until 1922, the area was largely a part of Austria-Hungary. After becoming Polish, which follows the Latin Rite, Polonisation and significant problems for all Orthodox, including united Christians developed. Some Ruthenians resisting Polonisation, felt deserted by the Vatican and returned to the Orthodox Church. After World War II, in 1945, Polish and Slovakian areas became part of the Soviet Union, which exerted pressure on the Ruthenians and other Ukrainians united with Rome, to sever relations and join the Orthodox Church, headed the Patriarch of Moscow. It was claimed that (1) the union with Rome was a Polish conspiracy to dominate and wipe out the culture of the Ukrainian Greek Catholic Church: (2) United orthodox faithful and priests had to suffer under Polish bishops of the Latin Rite and Polonisation. (3) But now they are liberated by the glorious Soviet Army under the leadership of the incomparable Marshal Joseph Stalin and therefore, continued ties to Rome are no longer necessary. The new Patriarch Alexius I called on Catholics for a separation from Rome:

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