Ugolino di Conti (Gregory IX) elected Pope

Born about 1145, at Anagni in the Campagna; died 22 August, 1241, at Rome. He received his education at the Universities of Paris and Bologna. After the accession of Innocent III to the papal throne, Ugolino, who was a nephew of Innocent III, was successively appointed papal chaplain, Archpriest of St. Peter's, and Cardinal-Deacon of Saint' Eustachio in 1198. In May, 1206, he succeeded Octavian as Cardinal-Bishop of Ostia and Velletri. A year later he and Cardinal Brancaleone were sent as papal legates to Germany to mediate between Philip of Swabia and Otto of Brunswick, both of whom laid claim to the German throne subsequent to the death of Henry VI. By order of the pope the legates freed Philip from the ban which he had incurred under Pope Celestine III on account of invading the Pontifical States. Though the legates were unable to induce Otto of Brunswick to give up his claims to the throne, they succeeded in effecting a truce between the two claimants and returned to Rome in 1208 to treat with the pope concerning their future procedure. On their way back to Germany early in June, 1208, they were apprised at Verona that Philip had been murdered, and again returned to Rome. Early in January, 1209, they again proceeded to Germany with instructions to induce the princes to acknowledge Otto of Brunswick as king. They were successful in their mission and returned to Rome in June of the same year. After the death of Pope Innocent III, 16 July, 1216, Ugolino was instrumental in the election of Pope Honorius III on 18 July. In order to hasten the choice the College of Cardinals had agreed to an election by compromise and empowered Cardinals Ugolino and Guido of Preneste to appoint the new pope.

In January, 1217, Honorius III made Ugolino plenipotentiary legate for Lombardy and Tuscia, and entrusted him with preaching the crusade in those territories. In this capacity he became a successful mediator between Pisa and Genoa, in 1217, between Milan and Cremona in 1218,...

Pope Gregory IX, born Ugolino di Conti, was pope from March 19, 1227 to August 22, 1241.
The successor of Pope Honorius III (1216–27), he fully inherited the traditions of Pope Gregory VII (1073–85) and of his uncle Pope Innocent III (1198-1216), and zealously continued their policy of Papal supremacy.

Gregory IX began his pontificate by suspending the Emperor, then lying sick at Otranto, for dilatoriness in carrying out the promised Sixth Crusade. The suspension was followed by excommunication and threats of deposition, as deeper rifts appeared – Frederick II's control of the Sicilian Church, his feudal obligations to the Pope, even his continued presence in Sicily. Frederick II publicly appealed to the sovereigns of Europe complaining of his treatment. Frederick II went to the Holy Land and skirmished with the Saracens to fulfill his vow, but was soon back in Italy, where Gregory IX had taken advantage of his absence by invading his territories. A consequent invasion of the Papal states in 1228 having proved unsuccessful, the Emperor was constrained to give in his submission and beg for absolution.
Although peace was thus secured (August 1230) for a season, the Roman people were far from satisfied; driven by a revolt from his own capital in June 1232, the Pope was compelled to take refuge at Anagni and invoke the aid of Frederick II. Gregory IX and Hohenstaufen came to a truce, but when Frederick II defeated the Lombard League in 1239, the possibility that he might dominate all of Italy, surrounding the Papal States, became a very real threat. A new outbreak of hostility led to a fresh excommunication of the emperor in 1239, and to a prolonged war.
Gregory IX denounced Frederick II as a heretic and summoned a council at Rome to give point to his anathema, at which Frederick II attempted to capture or sink as many ships carrying prelates to the synod as he could. Eberhard II von Truchsees, Prince-Archbishop of Salzburg in 1241 at the Council of Regensburg ...