Summi Pontificatus is an encyclical of Pope Pius XII published on 20 October 1939. The encyclical is subtitled "On the Unity of Human Society." It was the first encyclical of Pius XII and was seen as setting "a tone" for his papacy. It critiques major errors at the time, such as ideologies of racism, cultural superiority and the totalitarian state. It also sets the theological framework for future encyclical letters, such as Mystici corporis Christi (1943). The encyclical laments the destruction of Poland, denounces the Molotov-Ribbentrop Pact, and calls for a restoration of independent Poland.