Pope Urban IV, born Jacques Pantaléon around 1195, served as the head of the Roman Catholic Church from 1261 until his death in 1264. He was a French cleric and a member of the Dominican Order, known for his efforts to reform the Church and strengthen its authority. Urban IV is best remembered for instituting the feast of Corpus Christi, which celebrates the presence of Christ in the Eucharist. During his papacy, Urban IV faced significant challenges, including political conflicts in Italy and the ongoing Crusades. He sought to unite Christian forces against Muslim powers in the Holy Land, particularly in response to the fall of Jerusalem in 1244. His reign was marked by a commitment to spiritual renewal and the promotion of the Church's influence in Europe.