Pope Gregory XV (234º): Biography, Pontificate & Legacy

Who Was Pope Gregory XV?

Gregory XV holds the 234º place among Roman pontiffs, with a recorded reign of 9 February 1621–8 July 1623 inside the early modern and Counter-Reformation era. 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 Gregory XV in context.

Early Life & Background

Before election he was known as Alessandro Ludovisi. Born 9 January 1554 Bologna, Papal States, he entered a world shaped by politics and piety very different from today's global Church.

Historical Context

Gregory XV (#undefined) guided Catholics through Trent's reforms, global missions, and nation-states that challenged older papal temporal claims.

Pontificate & Key Events

The pontificate (9 February 1621–8 July 1623) centered on governance during the early modern and Counter-Reformation era. Established the Congregation for the Propagation of the Faith(1622). Issued the apostolic constitution Omnipotentis Dei (1623) against magicians and witches.

Papal Acts & Achievements

Acts associated with Gregory XV (#234, 9 February 1621–8 July 1623) 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

• 234th pope of the Catholic Church
• Pontificate: 9 February 1621–8 July 1623
• Issued the bull Aeterni Patris Filius(1621), which imposed conclaves to be by secret ballot.
• Issued the apostolic constitution Omnipotentis Dei (1623) against magicians and witches.

Legacy in the Catholic Church

Gregory XV remains pope 234º in the Annuario Pontificio. Set against the early modern and Counter-Reformation era, Gregory XV's choices show both the limits of any one pontiff and the continuity of the office he held.

Why Catholics Study This Pope Today

Catholics who open a page on Gregory XV usually want more than a birth-death line — they want to know what #234 did inside the early modern and Counter-Reformation era. Start with the concrete record: Issued the bull Aeterni Patris Filius(1621), which imposed conclaves to be by secret ballot. Established the Congregation for the Propagation of the Faith(1622). 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 Gregory XV's reign looks unique or typical for the early modern and Counter-Reformation era.

Place in the Line of Succession

Gregory XV followed Pope Paul V (233º, 16 May 1605–28 January 1621) after a transition shaped by the politics and piety of their shared century. He was followed by Pope Urban VIII (235º, 6 August 1623–29 July 1644), 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.