|original name Achille Ratti. 1857--1939, Italian ecclesiastic; pope (1922--39). He signed the Lateran Treaty (1929), by which the Vatican City was recognized as an independent state. His encyclicals condemned Nazism and Communism|
Italian pope from 1922 to 1939, one of the most important modern pontiffs whose motto "the peace of Christ in the Kingdom of Christ" illustrated his work to construct a new Christendom based on world peace.
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