Blessed Pope Gregory X (†1276) was head of the Catholic Church and ruler of the Papal States from 1 September 1271 to his death and was a member of the Secular Franciscan Order. He convened the Second Council of Lyon and also made new regulations regarding the papal conclave. Gregory's regulations on the conduct of the conclave remained in force until the 20th century. Pope Clement XI beatified Gregory X in 1713. He was made a patron of the Diocese of Arezzo and of Franciscan tertiaries. His cause of canonization resumed in 1944 under Pope Pius XII and remains open, with the requirement of a miracle attributed to his intercession needed for his canonization. His feast is commemorated on 10 January.