Person

Pope Gregory IX

d. 1241 · 13th century · Also known as Ugolino di Conti

Gregory IX was pope from 1227 to 1241, a relative of Innocent III. He repeatedly excommunicated Emperor Frederick II and fought him for control of Italy, and from 1231 he appointed papal inquisitors to pursue heresy. He canonised Francis of Assisi and Dominic, and in 1234 issued the Decretals, a major collection of canon law.

Pope Gregory IX
Image: Francesco Bini · CC BY-SA 4.0 · Wikimedia Commons

Mentioned in 1 profile

State of the Teutonic OrderFoundation

Mentioned in 1 state history

Republic of Noli

See also

Cite this entry
APA
The Epoch Institute. (2026). Pope Gregory IX. In The Epoch Institute Encyclopedia. https://the-epoch-institute.org/encyclopedia/pope-gregory-ix
MLA
“Pope Gregory IX.” The Epoch Institute Encyclopedia, The Epoch Institute, 2026, https://the-epoch-institute.org/encyclopedia/pope-gregory-ix. Accessed .
Chicago
The Epoch Institute. “Pope Gregory IX.” The Epoch Institute Encyclopedia. 2026. https://the-epoch-institute.org/encyclopedia/pope-gregory-ix.
Harvard
The Epoch Institute (2026) ‘Pope Gregory IX’, The Epoch Institute Encyclopedia. Available at: https://the-epoch-institute.org/encyclopedia/pope-gregory-ix (Accessed: ).

Last reviewed October 2026Random entry ↻