Pope Pius XI (), born Ambrogio Damiano Achille Ratti (; 31 May 1857 – 10 February 1939), was the Bishop of Rome and supreme pontiff of the Catholic Church from 6 February 1922 to 10 February 1939. He also became the first sovereign of the Vatican City State upon its creation as an independent state on 11 February 1929. He remained head of the Catholic Church until his death in February 1939. His papal motto was "Pax Christi in Regno Christi", translated as "The Peace of Christ in the Reign of Christ". Wikipedia
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