pius xi

noun

1. Achille Ratti, 1857–1939, Italian ecclesiastic: pope 1922–39.

noun

1. 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