He strengthened the central power of the Holy See and Roman Curia over the worldwide Catholic Church, while also formalizing the pope's ultimate doctrinal authority (the dogma of papal infallibility defined in 1870).

An unreliable account published many years later[5] suggests that the young Count Mastai was engaged to the daughter of the (Protestant) Church of Ireland Bishop of Kilmore, William Foster.

Shortly before his death, Pius VII – following Chilean leader Bernardo O'Higgins' wish to have the Pope reorganize the Catholic Church of the new republic – named him auditor to assist the apostolic nuncio, Monsignore Giovanni Muzi, in the first mission to post-revolutionary South America.

[7] The following year he was moved to the more prestigious Diocese of Imola, was made a cardinal in pectore in 1839, and in 1840 was publicly announced as cardinal-priest of Santi Marcellino e Pietro al Laterano.

[10] Cardinal Mastai-Ferretti was considered a liberal during his episcopate in Spoleto and Imola because he supported administrative changes in the Papal States and sympathized with the nationalist movement in Italy.

Faced with a deadlock and urgently persuaded by Bernetti to reject Lambruschini, liberals and moderates decided to cast their votes for Mastai-Ferretti, in a move that contradicted the general mood throughout Europe.

[17] While his political views and policies were hotly debated in the coming years, his personal lifestyle was above reproach, a model of simplicity and poverty in everyday affairs.

[18] Cardinal Mastai Ferretti entered the papacy in 1846, amidst widespread expectations that he would be a champion of reform and modernization in the Papal States, which he ruled directly, and in the entire Catholic Church.

[19] The most notable event in Pius IX's long pontificate was the end of the Papal States, which lay in the middle of the "Italian boot" around the central area of Rome.

[21] After the First Vatican Council concluded, an emissary of the Roman Curia was dispatched to secure the signatures of Patriarch Gregory II Youssef and the rest of the Melkite delegation who had voted non placet at the general congregation and left Rome prior to the adoption of the dogmatic constitution Pastor aeternus on papal infallibility.

The ecclesiastical policies of Pius IX were dominated by defence of the rights of the church and the free exercise of religion for Catholics in countries such as Russia and the Ottoman Empire.

Noteworthy elevations included Vincenzo Pecci (his eventual successor Leo XIII); Nicholas Wiseman of Westminster; the convert Henry Edward Manning; and John McCloskey, the first American cardinal.

Also in 1868, Pius IX offered the cardinalate to the Bishop of Concepción José Hipólito Salas whom he had met during the First Vatican Council, inviting him to join the Roman Curia.

Ignaz von Döllinger, a fervent critic of Pius' infallibility dogma, considered the political regime of the pope in the Papal States "wise, well-intentioned, mild-natured, frugal and open for innovations".

In the period before the 1848 revolutions, Pius was a most ardent reformer advised by such innovative thinkers as Antonio Rosmini (1797–1855), who reconciled the new free-thinking concerning human rights with the classical natural law tradition of the church's political and economic teaching on social justice.

Pius IX is credited with systematic efforts to improve manufacturing and trade by giving advantages and papal prizes to domestic producers of wool, silk and other materials destined for export.

[48] In a calculated, well-prepared move, Prime Minister Rossi was assassinated on 15 November 1848, and in the days following, the Swiss Guards were disarmed, making the Pope a prisoner in his palace.

[51] After the suppression of the republic later that year, Pius appointed a conservative government of three cardinals known as the Red Triumvirate to administer the Papal States until his return to Rome in April 1850.

[53] Italy instituted the Law of Guarantees (13 May 1871) which gave the Pope the use of the Vatican but denied him sovereignty over this territory, nevertheless granting him the right to send and receive ambassadors and a budget of 3.25 million lira annually.

Pius IX officially rejected this offer (encyclical Ubi nos, 15 May 1871), since it was a unilateral decision which did not grant the papacy international recognition and could be changed at any time by the secular parliament.

He excommunicated the nation's leaders, including King Victor Emmanuel II, whom he denounced as "forgetful of every religious principle, despising every right, trampling upon every law," whose reign over Italy was therefore "a sacrilegious usurpation.

[55] With French Emperor Napoleon III's military intervention in Mexico and establishment of the Second Mexican Empire under Maximilian I in 1864, the church sought relief from a friendly government after the anti-clerical actions of Benito Juárez, who had suspended payment on foreign debt and seized ecclesial property.

He re-established the Catholic hierarchy in England and Wales, under the newly appointed Archbishop and Cardinal Nicholas Wiseman with 12 additional episcopal seats: Southwark, Hexham, Beverley, Liverpool, Salford, Shrewsbury, Newport, Clifton, Plymouth, Nottingham, Birmingham, and Northampton.

[69] Pope Pius IX approved on 7 February 1847 the unanimous request of the American bishops that the Immaculate Conception be invoked as the Patroness of the United States of America.

Beginning in October 1862, the Pope began sending public letters to Catholic leaders in the United States calling for an end to the "destructive Civil War.

[77] In Germany, the state of Prussia, under the leadership of Otto von Bismarck, saw Catholicism as a dangerous foreign influence, and in 1872–1878 fought hard to reduce the power of the pope and the bishops.

[86][full citation needed] On 8 December 1854, he promulgated the apostolic constitution Ineffabilis Deus, defining the dogma of the Immaculate Conception of the Blessed Virgin Mary.

Without Italian opposition, Pope John Paul II declared Pius IX to be Venerable on 6 July 1985 (upon confirming his life of heroic virtue), and beatified him on 3 September 2000 (his annual liturgical commemoration is 7 February, the date of his death).

The beatification of Pius IX was controversial and was criticized by some Jews and Christians because of what was perceived as his authoritarian, reactionary politics; the accusation of abuse of episcopal powers; and antisemitism (most specifically the case of Edgardo Mortara, but also his reinstituting the Roman ghetto).

[100] Politically, he suffered the isolation of the papacy from most major world powers: "the prisoner of the Vatican" had poor relations with Russia, Germany, the United States, and France, and open hostility with Italy.