Pope Urban IV (; c. 1195 – 2 October 1264), born Jacques Pantaléon, was the head of the Catholic Church and ruler of the Papal States from 29 August 1261 to his death. He was not a cardinal; only a few popes since his time have not been cardinals, including Gregory X, Urban V and Urban VI. Early career Pantaléon was the son of a cobbler of Troyes, France. He studied theology and common law in Paris and was appointed a canon of Laon and later Archdeacon of Liège. At the First Council of Lyon (1245) he attracted the attention of Pope Innocent IV, who sent him on two missions in Germany. One of the missions was to negotiate the Treaty of Christburg between the pagan Prussians and the Teutonic Knights. He became Bishop of Verdun in 1253. In 1255, Pope Alexander IV made him Latin Patriarch of Jerusalem. Pantaléon had returned from Jerusalem, which was in dire straits, and was at Viterbo seeking help for the oppressed Christians in the East when Alexander IV died. After a three-month vacancy, Pantaléon was chosen by the eight cardinals of the Sacred College to succeed him in a papal election that concluded on 29 August 1261. He chose the regnal name of Urban IV. Pontificate A month before Urban's election, the Latin Empire of Constantinople, founded during the ill-fated Fourth Crusade against the Byzantines, fell to the Byzantines led by Emperor Michael VIII Palaiologos. Urban IV endeavoured without success to stir up a crusade to restore the Latin Empire. Georgius Pachymeres reports that Urban flayed one of Michael's envoys alive. Urban initiated construction of the Basilica of St. Urbain, Troyes, in 1262. The festival of Corpus Christi ("the Body of Christ") was instituted by Urban on 11 August 1264, with the publication of the papal bull Transiturus. Urban asked Thomas Aquinas, the Dominican theologian, to write the texts for the Mass and Office of the feast. This included such famous hymns as the Pange lingua, Tantum ergo, and Panis angelicus. Urban became involved in the affairs of Denmark. Jakob Erlandsen, Archbishop of Lund, wanted to make the Danish Church independent of the Royal power – which put him in direct confrontation with the Dowager Queen Margaret Sambiria, acting as regent for her son, King Eric V of Denmark. The Queen imprisoned the Archbishop, who responded by issuing an interdict. Both sides tried