The Decretals of Gregory IX (Latin, Decretales Gregorii IX), also collectively called the Liber extra, are an important source of medieval Canon Law. In 1230, Pope Gregory IX ordered his chaplain and confessor, St. Raymond of Peñaforte (Pennafort), a Dominican, to form a new canonical collection destined to replace all former collections. It has been said that the pope by this measure wished especially to emphasize his power over the Universal Church. After the invention of printing, the Decretals of Gregory IX were first published at Strasburg from the press of Heinrich Eggesteyn.
Pope Gregory IX (Latin: Gregorius IX; c. 1145 – 22 August 1241), born Ugolino di Conti, was Pope from 19 March 1227 to his death in 1241. He is known for issuing the Decretales and instituting the Papal Inquisition, a mechanism that severely punished people accused of heresy, in response to the failures of the episcopal inquisitions established during the time of Pope Lucius III through his papal bull Ad abolendam issued in 1184.
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