Early life and career
Achille Ratti was born in
Desio, in the
province of Milan, in 1857, the son of an owner of a
 He was ordained a priest in 1879 and embarked on an academic career within the Church. He obtained three doctorates (in philosophy,
canon law and theology) at the
Gregorian University in
Rome, and then from 1882 to 1888 was a professor at the seminary in
Padua. His scholarly specialty was as an expert
paleographer, a student of ancient and medieval Church manuscripts. Eventually, he left seminary teaching to work full-time at the
Ambrosian Library in
Milan, from 1888 to 1911.
During this time, he edited and published an edition of the
Missal (the rite of Mass used in Milan), and researched and wrote much on the life and works of St.
Charles Borromeo. He became chief of the Library in 1907 and undertook a thorough programme of restoration and re-classification of the Ambrosian's collection. He was also an avid
mountaineer in his spare time, reaching the summits of
Monte Rosa, the
Mont Blanc and
Presolana. The combination of a scholar-athlete pope would not be seen again until the pontificate of
John Paul II. In 1911, at
Pope Pius X's (1903–1914) invitation, he moved to the Vatican to become Vice-Prefect of the
Vatican Library, and in 1914 was promoted to Prefect.
Nuncio to Poland and Expulsion
Ratti (centre) circa 1900 in the Alps on a tour.
The young Ratti as a newly ordained priest
Pope Benedict XV (1914–1922) asked him to change careers and take a diplomatic post:
apostolic visitor (that is, unofficial papal representative) in
Poland, a state newly restored to existence, but still under effective German and
Austro-Hungarian control. In October 1918, Benedict was the first head of state to congratulate the Polish people on the occasion of the restoration of their independence.
 In March 1919, he nominated ten new bishops and, soon after, upgraded Ratti's position in Warsaw to the official position of
 Ratti was consecrated as a
titular archbishop in October 1919.
Benedict XV and Nuncio Ratti repeatedly cautioned Polish authorities against persecuting the Lithuanian and
 During the Bolshevik advance against
Warsaw, the Pope asked for worldwide public prayers for Poland, while Ratti was the only foreign diplomat who refused to flee Warsaw when the
Red Army was approaching the city in August 1920.
 On 11 June 1921, Benedict XV asked Ratti to deliver his message to the Polish episcopate, warning against political misuses of spiritual power, urging again peaceful coexistence with neighbouring people, stating that “love of country has its limits in justice and obligations”.
Ratti intended to work for
Poland by building bridges to men of goodwill in the
Soviet Union, even to shedding his blood for Russia.
 Benedict, however, needed Ratti as a diplomat, not as a
martyr, and forbade his traveling into the USSR despite his being the official papal delegate for Russia.
 The nuncio's continued contacts with Russians did not generate much sympathy for him within Poland at the time. After Pope Benedict sent Ratti to
Silesia to forestall potential political agitation within the Polish Catholic clergy,
 the nuncio was asked to leave Poland. On 20 November, when German Cardinal
Adolf Bertram announced a papal ban on all political activities of clergymen, calls for Ratti's expulsion climaxed.
 Ratti was asked to leave. “While he tried honestly to show himself as a friend of Poland, Warsaw forced his departure, after his neutrality in Silesian voting was questioned”
 by Germans and Poles. Nationalistic Germans objected to the Polish nuncio supervising local elections, and patriotic Poles were upset because he curtailed political action among the clergy.
Achille Ratti, shortly after his consecration as bishop
Elevation to the papacy
Pius XI makes his first public appearance as pope in 1922. The coat of arms on the banner is that of
Pope Pius IX
consistory of 3 June 1921, Pope Benedict XV created three new cardinals, including Achille Ratti, who was appointed
Archbishop of Milan simultaneously. The pope joked with them, saying, "Well, today I gave you the red hat, but soon it will be white for one of you."
 After the Vatican celebration, Ratti went to the Benedictine monastery at
Monte Cassino for a retreat to prepare spiritually for his new role. He accompanied Milanese pilgrims to
Lourdes in August 1921.
 Ratti received a tumultuous welcome on a visit to his home town
Desio, and was enthroned in Milan on 8 September. On 22 January 1922, Pope Benedict XV died unexpectedly of
At the conclave to choose a new pope, which proved to be the longest of the 20th century, the College of Cardinals was divided into two factions, one led by
Rafael Merry del Val favoring the policies and style of Pope Pius X and the other favoring those of Pope Benedict XV led by
Gasparri approached Ratti before voting began on the third day and told him he would urge his supporters to switch their votes to Ratti, who was shocked to hear this. When it became clear that neither Gasparri nor del Val could win, the cardinals approached Ratti, thinking him a compromise candidate not identified with either faction. Cardinal
Gaetano de Lai approached Ratti and was believed to have said: "We will vote for Your Eminence if Your Eminence will promise that you will not choose Cardinal Gasparri as your secretary of state". Ratti is said to have responded: "I hope and pray that among so highly deserving cardinals the Holy Spirit selects someone else. If I am chosen, it is indeed Cardinal Gasparri whom I will take to be my secretary of state".
Ratti was elected pope on the conclave's fourteenth ballot on 6 February 1922 and took the name "Pius XI", explaining that Pius IX was the pope of his youth and Pius X had appointed him head of the Vatican Library. It was rumoured that immediately after the election, he decided to appoint Pietro Gasparri as his
Cardinal Secretary of State.
As his first act as pope, he revived the traditional public blessing from the balcony,
Urbi et Orbi ("to the city and to the world"), abandoned by his predecessors since the loss of Rome to the Italian state in 1870. This suggested his openness to a rapprochement with the government of Italy.
 Less than a month later, considering that all four cardinals from the Western Hemisphere had been unable to participate in his election, he issued
Cum proxime to allow the College of Cardinals to delay the start of a conclave for as long as eighteen days following the death of a pope.