Leo XIII
Pope Leo XIII, born Vincenzo Gioacchino Pecci in 1810, served as the head of the Roman Catholic Church from 1878 until his death in 1903. His early life was marked by a strong educational foundation, culminating in his ordination to the priesthood in 1837. Before becoming pope, Pecci held various significant ecclesiastical roles, including archbishop and nuncio, where he developed a conservative stance against liberalism and socialism. Elected as pope at the age of 68, he was initially perceived as a transitional figure, but he surprised many with his lengthy and impactful papacy.
Leo XIII is renowned for his encyclicals that addressed social issues, most notably "Rerum Novarum," which advocated for workers' rights and fair wages in the context of an industrialized society. His approach combined a commitment to traditional Catholic doctrine with an understanding of the modern world, positioning him as a reconciler of faith and contemporary societal challenges. He also emphasized the importance of education, encouraging the study of the natural sciences and Thomist philosophy. Despite facing numerous challenges in relations with various governments, he is often celebrated as one of the most significant popes in modern history for his efforts to adapt the Church to the realities of the 19th century. Leo XIII's legacy continues to influence Catholic thought and social teaching.
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Leo XIII
Roman Catholic pope (1878-1903)
- Born: March 2, 1810
- Birthplace: Carpineto Romano, Papal States (now in Italy)
- Died: July 20, 1903
- Place of death: Rome, Italy
Considered one of the greatest leaders of the Roman Catholic Church during a period of crisis, Pope Leo XIII tried to maintain the strength and power of the Church in a world changing through industry, colonization, and governmental upheaval. He was not always successful, but he was a pioneer, aware of the needs of the modern Church.
Early Life
Pope Leo XIII was born Vincenzo Gioacchino Pecci in the hills south of Rome in central Italy. His parents, Colonel Ludovico Pecci and Anna Prosperi Buzi, were patrician, but neither wealthy nor of great nobility. The sixth in a family of seven children, Pecci began his education in Viterbo at the Jesuit college from 1818 to 1824. He was a brilliant student, with what became lifelong scholarly achievement in Latin. He continued his studies in Rome from 1824 to 1832 at the Roman College and in 1832 was admitted to the Academy of the Noble Ecclesiastics. He completed his religious studies at the University of the Sapienza between 1832 and 1837, concentrating in theology and civil and canon law. He was ordained in 1837.
In the same year, he was appointed a domestic prelate, and in 1838 he was named governor or apostolic delegate of Benevento by Pope Gregory XVI, who had praised Pecci’s courageous service during the cholera epidemic of 1837. His success in this position, especially in reducing banditry and eliminating the inroads being made by liberals, led to his appointment in 1841 to the same position in Perugia. Although this area had similar problems to solve, Pecci went beyond his previous successes and improved the economy by building roads, establishing a farmers’ savings bank, and gaining great popularity among the residents.
With these achievements, Pecci was sent to Belgium as nuncio, the pope’s representative, in January, 1843, after having been consecrated titular archbishop of Damietta. Pecci spent three difficult years in Belgium, which finally ended when King Leopold requested of the pope that Pecci be recalled. The king and his prime minister, Nothomb, had been seeking to confer the right to name members of the university juries to the government. In this matter, crucial to the educational system of Belgium, Pecci sided with the bishops and Catholic politicians in opposition to the king. Even though the Catholic side won, the victory was empty for Pecci. Although this period appears to have been a failure, Pecci gained experience that helped form his future conservatism. During this time, his only extended observation of the more industrialized, liberal areas of Europe, he saw the behavior of a liberal political regime toward Catholics and learned to oppose it. As he fought against unionism, the compromise and agreement between Catholics and moderate liberals in Belgium, he came to be wary of liberal hands extended in compromise.
Life’s Work
When Pecci left Belgium, he returned to Perugia, where he served as archbishop until 1878 and further solidified many of the ideologies that would serve him during his pontificate. Along with his brother Joseph, a Jesuit seminary professor, he worked to increase the numbers of clerics; modernize the curriculum at the seminaries; revive Thomism, the medieval Scholasticism based on the Aristotelianism of Thomas Aquinas; and establish the Academy of Saint Thomas in 1859. As a result of these activities, Pecci was named a cardinal in 1853.

During the period that he was archbishop in Perugia, Pecci was politically prudent and reserved. He protested the annexation of Perugia by the kingdom of Sardinia in 1860; on the other hand, he would not join Cardinal Giacomo Antonelli, the secretary of state to Pope Pius IX, in his methods of government and involvement in conflicts. Consequently, Antonelli considered Pecci an enemy and kept him from Rome. Following his moderate views as a Catholic, Pecci wrote his pastoral letters of 1874-1877, recommending that the Roman Catholic Church make conciliatory gestures toward contemporary society. Self-evident as it may seem, he recognized that the Church did not exist in a void, but rather in the quickly changing world of the late nineteenth century. These letters, in addition to his other achievements, gained for him the respect of Pius, and, when Antonelli died in 1877, Pecci was summoned to serve as camerlengo in the Roman curia, the chamberlain who oversees the Church when the pope dies.
When Pius died in 1878, Pecci was in a good position to be elected pope. Because this was the first conclave since the Holy See had lost its temporal power, Pecci’s role as the leading moderate was important. He was indeed elected on the third ballot with forty-four of the sixty-one votes, after having received a plurality on the first ballot of nineteen votes, thirteen more than the second most favored candidate.
When he became Pope Leo XIII, Pecci was sixty-eight years old and in fragile health. These facts, combined with his delicate appearance, all indicated that his would be, at best, a brief transitional appointment. However, he was popular. Because the Italian government feared demonstrations in his support in St. Peter’s Square and all over Rome, his crowning took place in private on March 3 in the Sistine Chapel so that he would not appear publicly on the loggia to bless the people as he wished to do.
Leo’s acts on the evening of his coronation, however, foreshadowed the theme of his reign. He wrote letters to the German emperor, the Swiss president, and the Russian czar announcing his election and offering hope that the Church might come to better accord with their governments. Although doctrinally conservative, he sought to maintain a strong role for the Church in the modern world.
In the course of his papacy, Leo wrote numerous encyclicals on subjects ranging from traditional piety to social issues. He wrote eleven encyclicals on the Blessed Virgin Mary and the Rosary, two each on the Eucharist and the redemptive work of Christ, and one on the renewal of the Franciscan Third Order. In the Jubilee Year of 1900, he consecrated the entire human race to the Sacred Heart of Jesus, an initiative begun by Pius, and in 1893 instituted a feast of the Holy Family. Becoming more conservative in the final few years or his life, he published new norms for censorship in 1897 and a new Index in 1900, and he set up a permanent Biblical Commission in 1902 after writing the encyclical on Bible study, Providentissimus Deus (1893; On the Study of the Scriptures , 1894).
Leo’s ability to align such conservative piety to a new recognition of modern states is quite remarkable. It was accomplished, however, not with statements of accord with government, but rather with statements only of recognition. In 1878, the year of his coronation, Leo attacked socialism, communism, and nihilism in Quod apostolici muneris (Concerning Modern Errors, Socialism, Communism, Nihilism , 1895), and, in 1884, he wrote similarly on Freemasonry. He also acted to increase centralization within the Church, much to the disappointment of progressives.
At the same time, Leo wrote encyclicals on the relationship of the Church to sociopolitical order: Diuturnum illud (1881; On Civil Government , 1942) recognized the existence of democracy in God’s world, Immortale Dei (1885; On the Christian Constitution of States , 1885) defined the spiritual and temporal spheres of power, and Libertas praestantissimum (1888; Human Liberty , 1895) viewed the Church as the true source of liberty. Most important was Rerum novarum (1891; The Condition of Labor , 1891), which advocated private property rights, fair wages, workers’ rights, and trade unionism, while, predictably, condemning socialism and economic liberalism. Because of the positions presented in this encyclical, Leo came to be known as “the workers’ pope.”
In addition to these, Leo wrote encyclicals on social and intellectual issues. Arcanum divinae sapientia (1880; On Christian Marriage , 1880) is a highly conservative statement on marriage, identical in tone and thought to writings of his predecessors. On intellectual matters, however, he was more open to new ideas than the revival of old ones. Following his lifelong respect for and study of Thomism, he encouraged Catholics to incorporate fully Thomist metaphysics into Catholic philosophy in Aeterni patris (1879; Scholastic Philosophy , 1879). Leo also bridged the gap between Catholicism and the natural sciences by encouraging Catholics to study astronomy and the other natural sciences. He urged complete objectivity in all areas of scholarship done by Catholics; in an unprecedented ecumenical spirit, he opened the Vatican libraries to scholars of all faiths in 1883. This was begun in 1879, when he allowed the German historian Ludwig Pastor access to the secret archives of the Vatican.
In many ways, Leo was a far more political pope than was his successor, yet while he and his four secretaries of state had many diplomatic successes, he failed in matters closest to home, such as the achievement of accord with the Italian government. By 1887, Leo was willing to accept a compromise in which Italy would be entirely unified under the House of Savoy; the Papal States, a sixteen-thousand-square-mile area in central Italy, would be given to Italy; and an indemnification or compensation, offered under the Law of Guarantee, therefore would be received from Italy. The Italian government, however, wanted the abdication of the pope’s sovereignty, which would lead inevitably to limited freedom for Leo himself and future popes. He made a counterrequest for a repeal of the anticlerical laws and restoration of papal rule for Rome, but it was denied. Thus, Leo was unable to achieve any resolution of conflict with the Italian government. None, indeed, was attained until the Lateran Treaty of 1929.
France also presented problems for the pope. With its republican government, France sought the separation of church and state, along with secular, social, and educational systems. Catholics within France were not enthusiastic in their support for the Church against their government. Soon, government recognition of all religious groups was required or the groups were to be disbanded. In 1880, the Jesuits were dissolved, followed in 1900 by the Congregation of the Assumptionists. Teaching orders went into exile, and the pope was unable to turn the tide, which became a crisis for his successor, Pius X.
Relations with England remained unchanged. At the beginning of his reign, Leo initiated a study seeking possible reconciliation with the Anglican Church. When such a unification proved impossible, he issued an apostolic letter in 1896, discouraging any move in this direction; yet he was responsible for the cardinalship of John Henry Newman in 1878.
Leo actively sought a reunion with the Oriental and Slavic Catholic churches, going so far as to praise the work of Saint Cyril and Saint Methodius in the encyclical Grande munus (1880) and to discuss rites and reunion in the apostolic letter of 1894. Again, he was unable to make concrete advances in this direction.
More satisfactory were Leo’s efforts in Belgium, Germany, and Russia. He negotiated agreements with Belgium in 1884 and with Russia in 1894. In 1886-1887, he successfully achieved the repeal of the anticlerical laws in Germany (the Kulturkampf) and, in his sole diplomatic success, he mediated in Germany’s dispute with Spain over the possession of the Caroline Islands in the Pacific Ocean in 1885. He was, however, unsuccessful in his attempt to keep Germany and Austria from joining Italy in the Triple Alliance in 1887. He was not invited to the Hague Peace Conference of 1899, because of the intransigence of the Italian government.
In other areas of the world Leo recognized the importance of colonialism to Christian evangelism, and he approved 248 sees, 48 vicarates or prefectures, and 2 patriarchates in Scotland, North Africa, India, Japan, and the United States. Although he criticized “Americanism,” which would have attempted to modernize Catholicism, in a letter of 1899, he named the first apostolic delegate to the United States in 1892.
The twenty-five years of Leo’s reign ended in 1903 with his death at the age of ninety-three. He far exceeded expectations in the longevity, the social concern, and the intellectual strength of his service to the Church.
Significance
It was fortunate for the Roman Catholic Church that Leo XIII became the pope when the Western world was experiencing great turmoil. A brilliant man, he was able to steer the Church into a role in society that at once showed an awareness of the modern world but did not stray far from traditional church doctrine. The English writer Thomas Carlyle called him a great “reconciler of differences.” Leo’s was a strong voice against the growing popularity of socialism in Europe, yet he accepted democracy and advocated the rights of workers in the growing industrialized world.
Within his own church, Leo was able to create a clear role of spiritual leadership for the pope to replace the recently lost temporal powers of the Papacy. Although some scholars consider his learning antiquated, restricted, and perhaps obsessively concerned with Thomism, his intellectual breadth, strength of character, and devotion to service have brought him great praise. Even with his many failures, he is generally considered the greatest pope in three hundred years. Leo said of himself, “I want to set the church so far forward that my successor will not be able to turn back.” As a pioneer whose ideas shone even more brightly after his death, he clearly achieved this goal.
Bibliography
Bokenkotter, Thomas. “Social Catholicism and Christian Democracy.” In A Concise History of the Catholic Church. Garden City, N.Y.: Doubleday, 1927. A scholarly and detailed narrative of the political world into which Leo was thrust at his ordination. Leo’s charitable piety is shown as it affected the changing governments and economies of the entire Western world.
Burkle-Young, Francis A. Papal Elections in the Age of Transition, 1878-1922. Lanham, Md.: Lexington Books, 2000. Recounts how Leo XIII and his three successors rose to the papacy, providing previously unpublished details of church conclaves.
Gargan, Edward T., ed. Leo XIII and the Modern World. New York: Sheed & Ward, 1961. A series of nine essays by various scholars preceded by an introductory essay and followed by an extensive bibliography on Leo and his period in history. The essays stress Leo’s theological contributions, especially as a Thomist, and his impact on the European and American political worlds of the late nineteenth century.
Holland, Joe. Modern Catholic Social Teaching: The Popes Confront the Industrial Age, 1740-1958. New York: Paulist Press, 2003. This examination of the Vatican’s response to the Industrial Revolution includes a discussion of Rerum novarum, described as the first papal declaration of working people’s rights.
Kretzer, David I. Prisoner of the Vatican: The Popes’ Secret Plot to Capture Rome from the New Italian State. Boston: Houghton Mifflin, 2004. Using previously unopened Vatican archives, Kretzer recounts how Popes Pius IX, Leo XIII, and other members of the clergy sought to dismantle the new Italian state and regain control of Rome.
McCabe, Joseph. “Leo XIII.” In Crises in the History of the Papacy. New York: G. P. Putnam’s Sons, 1916. An objective appraisal of the life and accomplishments of Leo, which assesses him as the best pope in three hundred years but a failure in gaining influence upon the thoughts or actions of Western society.
Miller, J. Martin. The Life of Pope Leo XIII. Philadelphia: National Publishing, 1903. A five-hundred-page biography written in praise of Leo that was begun before his death, containing several drawings and photographs. The author writes conversationally and quaintly, quoting letters and relating anecdotes in dialogue. His purpose is the veneration of Leo, and nearly one-third of the book is devoted to a detailed description of Leo’s final illness and death.
O’Reilly, Bernard. Life of Leo XIII from an Authentic Memoir Furnished by His Order. New York: Charles L. Webster, 1887. Authorized biography written by a Roman Catholic priest and issued by Mark Twain’s own publishing firm.
Wallace, Lillian Parker. Leo XIII and the Rise of Socialism. Durham, N.C.: Duke University Press, 1966. A presentation of the juxtaposition of two major antagonistic ideologies of the nineteenth century, held on one side by Leo and his church and on the other by Karl Marx and his followers. This 464-page volume shows Leo’s power as he stems the tide of Marxism in Europe with his intellectual and compassionate approach to the social problems of the industrial world.