Pope Leo XII LEO Duodecimus (252º): Biography, Pontificate & Legacy

Who Was Pope Leo XII LEO Duodecimus?

Leo XII LEO Duodecimus holds the 252º place among Roman pontiffs, with a recorded reign of 28 September 1823–10 February 1829 inside the modern papacy. Subject and later the sovereign of the Papal States. What follows is a structured biography — early life, context, acts, and succession — written for Catholics who want Leo XII LEO Duodecimus in context.

Early Life & Background

Before election he was known as Annibale Francesco Clemente Melchiorre Girolamo Nicola della Genga. Born 22 August 1760 Genga, Papal States, he entered a world shaped by politics and piety very different from today's global Church.

Historical Context

Leo XII LEO Duodecimus (#undefined) served while industry, world wars, the loss of the Papal States, and Vatican councils remade how Rome speaks to a mass society.

Pontificate & Key Events

The pontificate (28 September 1823–10 February 1829) centered on governance during the modern papacy. Condemned Freemasonry and the Bible societies.

Papal Acts & Achievements

Acts associated with Leo XII LEO Duodecimus (#252, 28 September 1823–10 February 1829) still draw historians and Catholics who want more than a one-line summary. His reign remains a link in the succession now counted at 267 popes.

Key Highlights

• 252nd pope of the Catholic Church
• Pontificate: 28 September 1823–10 February 1829
• Shepherded the Church during the modern papacy
• Successor of St. Peter in the official Catholic list

Legacy in the Catholic Church

Leo XII LEO Duodecimus remains pope 252º in the Annuario Pontificio. Set against the modern papacy, Leo XII LEO Duodecimus's choices show both the limits of any one pontiff and the continuity of the office he held.

Why Catholics Study This Pope Today

Place Leo XII LEO Duodecimus on your mental map: 252º successor of Peter, reigning 28 September 1823–10 February 1829, formed by the modern papacy. Start with the concrete record: Placed the Catholic educational system under the control of the Jesuits through the bull Quod divina sapientia(1824). Where bulls, conciliar acts, or encyclicals survive from this reign, they repay readers who want primary sources rather than summaries alone. Use the neighboring pontiff links below to test whether Leo XII LEO Duodecimus's reign looks unique or typical for the modern papacy.

Place in the Line of Succession

Leo XII LEO Duodecimus followed Pope Servant of God Pius VII (251º, 14 March 1800–20 August 1823) after a transition shaped by the politics and piety of their shared century. He was followed by Pope Pius VIII (253º, 31 March 1829–30 November 1830), whose biography continues the chain on Guide Catholic. For the full chronological map, see our complete list of all 267 popes — then read neighboring biographies for contrast, not only continuity.