Who he was
A scholar-priest from near Milan, he was for many years a librarian at the Ambrosian Library and then Prefect of the Vatican Library, and a keen mountaineer who climbed Monte Rosa and Mont Blanc. Sent to Poland after the First World War, he became nuncio there and stayed at his post when the Bolshevik army approached Warsaw in 1920. He was briefly Archbishop of Milan and a cardinal before his election in 1922.
What he is remembered for
He settled the 'Roman Question' with Italy in the Lateran Treaty of 1929, which created the Vatican City State. His encyclicals included Quadragesimo anno on the social order and Casti connubii on marriage, and in 1937 he condemned Nazism in Mit brennender Sorge and atheistic Communism in Divini Redemptoris. He opened Vatican Radio with Marconi in 1931 and canonised St John Fisher, St Thomas More, St John Bosco and St Thérèse of Lisieux.
Sources
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