Pope Pius XI (Latin: Pius PP. XI; Italian: Pio XI, 31 May 1857–10 February 1939),  born Achille Ratti, was an Italian priest of the Roman Catholic Church and the 260th Pope from 1922 to 1939.[1]

Ratti was ordained as a priest in 1875.[2]

Father Ratti was a professor at the Padua Seminary from 1882 to 1888. He worked at Ambrosian Library of Milan from 1888 to 1911; and at the Vatican Library from 1911-1914.[2]

In 1919, Pope Benedict XV made Ratti a Bishop of Lepanto.[3]

In 1921, Benedict named him Archbishop of Milan.[2]

In 1921, Ratti was made a cardinal.[4]

Cardinal Ratti was elected pope on February 6, 1922; and he chose the name Pope Pius XI.[3]

Some of his decisions were controversial. He made 18 concordats (treaties) with foreign governments. They included the Lateran Concordat with Italy in 1929; and the Reichskoncordat with Germany in 1933.[5]

Media related to Pius XI at Wikimedia Commons

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