Pope Leo XIII (256º): Rerum Novarum, Social Teaching & Modern Papacy
Pontificate: 20 February 1878–20 July 1903
Leo XIII LEO Tertius Decimus was the 256th pope of the Catholic Church, reigning 20 February 1878–20 July 1903 during the modern papacy. First pope to be filmed using a motion picture camera(1898) and first pope with voice recorded.
Who Was Pope Leo XIII LEO Tertius Decimus?
This biography of Leo XIII LEO Tertius Decimus (256º) covers background, major events, and legacy in the line of St. Peter. Common search topics include Rerum Novarum. During the modern papacy, the Bishop of Rome exercised teaching, sanctifying, and governing authority for the universal Church.
Early Life & Background
Before election he was known as Gioacchino Vincenzo Raffaele Luigi Pecci. Born 2 March 1810 Carpineto Romano, French Empire, he entered a world shaped by politics and piety very different from today's global Church.
Historical Context
Leo XIII LEO Tertius Decimus served during the modern papacy — a time of industrial revolution, world wars, the loss of the Papal States, Vatican I and II, and the Church's engagement with democracy, human rights, and mass media.
Pontificate & Key Events
The pontificate (20 February 1878–20 July 1903) centered on governance during the modern papacy. Issued the encyclical Rerum novarum(1891), supporting Christian democracy against Communism. Approved two new Marian scapulars; first pope to fully embrace the concept of Mary as mediatrix.
Papal Acts & Achievements
Leo XIII LEO Tertius Decimus left a distinct mark through decisions that historians still debate and Catholics still study. French citizen of Italian ethnicity, later becoming a subject of the Papal States and finally an Italian citizen. Fourth-longest reigning pope after Peter, Pius IX, and John Paul II. Promoted the rosary and scapular. Oldest verified pope in office.
Key Highlights
- 256th pope of the Catholic Church
- Pontificate: 20 February 1878–20 July 1903
- Issued the encyclical Rerum novarum(1891), supporting Christian democracy against Communism.
- Approved two new Marian scapulars; first pope to fully embrace the concept of Mary as mediatrix.
- First pope to be filmed using a motion picture camera(1898) and first pope with voice recorded.
Legacy in the Catholic Church
Leo XIII LEO Tertius Decimus remains pope 256º in the Annuario Pontificio. Read against the modern papacy, his pontificate shows how Providence works through imperfect ministers without abandoning the Barque of Peter.
Why Catholics Study This Pope Today
Studying Leo XIII LEO Tertius Decimus helps Catholics see how the Holy Spirit guided the Church through the modern papacy — with human weakness and grace intertwined. Primary sources from this pontificate — bulls, conciliar acts, or encyclicals — reward readers who want depth beyond summaries. Place this pope in context using our chronological list of all 267 popes and the biographies of his immediate predecessor and successor linked below.
Place in the Line of Succession
Leo XIII LEO Tertius Decimus followed Pope Bl. Pius IX (255º) in the unbroken line of apostolic succession from St. Peter. Upon his death or resignation, he was succeeded by Pope St. Pius X (257º), who continued the mission of shepherding the universal Church. Explore the full chronological chain in our complete list of all 267 popes, or read the biographies of neighboring pontiffs linked below.