GREGORY IX  . (Ugolino Conti de Segni), pope from the 19th of March 1227, to the 22nd of August 1241, was a nobleman of Anagni and probably a nephew of Innocent III . He studied at Paris and Bologna, and,. having been successively archpriest of St Peter's, papal chaplain, cardinal-deacon of Sant' Eustachio, cardinal-bishop of Ostia, the first protector of the Franciscan order, and papal legate in Germany under Innocent III., and Honorius III., he succeeded the latter in the papacy . He had long been on friendly terms with the emperor Frederick II., but now excommunicated him (29th of September 1227) for continued neglect of his vows and refusal to undertake the crusade . When Frederick finally set out the following June without making submission to the pope, Gregory raised an insurrection against him in Germany, and forced him in 1230 to beg for absolution . The Romans, however, soon began a very bitter war against the temporal power and exiled the pope (1st of June 1231) . Hardly had this contest been brought to an end favourable to the papacy (May 1235) when Gregory came into fresh conflict with Frederick II . He again excommunicated the emperor and released his subjects from their allegiance (24th of March 1239) . Frederick, on his side, invaded the Papal States and prevented the assembling of a general council convoked for Easter 1241 . The work of Gregory, however, was by no means limited to his relations with emperor and Romans . He systematized the Inquisition and entrusted it to the Dominicans; his rules against heretics remained in force until the time of Sixtus V . He supported Henry III. against the English barons, and protested against the Pragmatic Sanction of Louis IX. of France .

He sent monks to

Constantinople to negotiate with the Greeks for church unity, but without result . He canonized Saints Elizabeth of Thuringia, Dominic, Anthony of Padua and Francis of Assisi . He permitted free study of the Aristotelian writings, and issued (1234), through his chaplain, Raymond of Pennaforte, an important new compilation of decretals which he prescribed in the bull Rex pacificus should be the standard text-book in canon law at the universities of Bologna and Paris . Gregory was famed for his learning and eloquence, his blameless life, and his great strength of character . He died on the 22nd of August 1241, while Frederick II. was advancing against him, and was succeeded by Celestine IV . For the life of Gregory IX., consult his Letters in Monumenta Germaniae historica, Epistolae saeculi XIII. e regestis pontif . Roman. selectee (Berlin, 1883) ; " Les Registres de Gregoire IX," ed . L . Auvray in Bibliotheque des ecoles francaises d'Athenes et de Rome (Paris, 1890—1905); A . Potthast, Regesta pontif . Roman . (Berlin, 1875) and " Registri dei Cardinali Ugolino d' Ostia et Ottaviano degli Ubaldini," ed .

G .

Levi in Fonti per la storia d' Italia (189o) . See J . Felten, Papst Gregor IX . (Freiburg i . B., 1886) ; J . Marx, Die Vita Gregorii IX. quellenkritisch untersucht (1889); P . Balan, Storia di Gregorio IX e dei suoi tempi (3 vols.,'Modena, 1872—1873) ; F . Gregorovius, Rome in the Middle Ages, vol . 5, trans. by Mrs G . W . Hamilton (London, 1900—1902); H .

H .

Milman, Latin Christianity, vol . 5 (London, 1899); R . Honig, Rapporti tra Federico II e Gregorio IX rispetto ally spedizione in Palestina (1896) ; P . T . Masetti, I Pontefici Onorio III, Gregorio IX ed Innocenzo IV a fronte dell' .Imperatore Federico II nel secolo XIII (1884); T . Frantz, Der grosse Kampf zwischen Kaisertum u . Papsttum zur Zeit des Hohenstaufen Friedrich II . (Berlin, 19o3); W . Norden, Das Papsttum u . Byzanz (Berlin, 1903) . An exhaustive bibliography and an excellent article on Gregory by Carl Mirbt are to be found in Hauck's Realencyklopddie, 3rd edition .

, GREGORY X . (Tebaldo

Visconti), pope from the 1st of September 1271, to the loth of January 1276, was born at Piacenza in 1208, studied for the church, and became archdeacon of Liege . The eighteen cardinals who met to elect a successor to Clement IV. were divided into French and Italian factions, which wrangled over the election for nearly three years in the midst of great popular excitement, until finally, stirred by the eloquence of St Bonaventura, the Franciscan monk, they entrusted the choice to six electors, who hit on Visconti, at that time accompanying Edward of England on the crusade . He returned to Rome and was ordained priest on the 19th of March 1272, and consecrated on the 27th . He at once summoned the fourteenth general council of the Catholic Church, which met at Lyons in 1274, with an attendance of some 1600 prelates, for the purpose of considering the eastern schism, the condition of the Holy Land, and the abuses in the church . The Greeks were persuaded, thanks to St Bonaventura, to consent to a union with Rome for the time being, and Rudolph of Habsburg renounced at the council all imperial rights in the States of the Church . The most celebrated among the many reform decrees issued by Gregory was the constitution determining for the first time the form of conclave at papal elections, which in large measure has remained ever since the law of the church . Gregory was on his way to Rome to crown Rudolph and send him out on a great crusade in company with the kings of England, France, Aragon and Sicily, when he died at Arezzo on the loth of January 1276 . He was a nobleman, fond of peace and actuated by the consciousness of a great mission . He has been honoured as a saint by the inhabitants of Arezzo and Piacenza . His successor in the papacy was Innocent V . The registers of Gregory X. have been published by J .

Guiraud in the Bibliotheque des ecales francaises d'Athenes et de Rome (Paris, 1892—1898) . See K . J. von Hefele, Conciliengeschichte, vol . 5, 2nd edition (1873—189o) ; H . Flake, Konzilienstudien z . Gesch. des z3ten Jahrhunderts (Miinster, 1891); P . Piacenza, Compendia della storia del b . Gregorio X, papa (Piacenza, 1876) ; F . Gregorovius, Rome in the Middle Ages, vol . 5, trans. by Mrs G . W . Hamilton (London, 1900—1902) ; II .

Otto, Die Beziehungen Rudolfs von Habsburgs zu Papst Gregor X . (Innsbruck, 1895); A Zisterer, Gregor X. u . Rudolf von Habsburg in ihren gegenseitigen Beziehungen (Freiburg i . B., 1891) ; F . Walter, Die Politik der Kline unter Gregor X . (Berlin , 1894) ; A . Potthast, Regesta pontif . Roman. vol . 2 (Berlin, 1875) ; W . Norden, Das Papsttum and Byzanz (Berlin, 1903) ; J . Loserth, Akten fiber die Wahl Gregors X." in Neues Archiv, xxi . (1895); A. von Hirsch-Gereuth, " Die Kreuzzugspolitik Gregors X." in Studien z .

Gesch. d . Kreuzzugsidee nach den Kreuzziigen (

Munich, 1896) . There is an excellent article by Carl Mirbt in Hauck's Realencyklopadie, 3rd edition .