Lyons, Second Council of, 1274, 14th ecumenical council of the Roman Catholic Church. It was summoned by Pope Gregory X to discuss problems in the Holy Land, to remove the schism of East and West, and to reform the church. The reunion of Constantinople and Rome had been proposed by the Byzantine emperor, Michael VIII, who hoped to avert the imperial designs of Charles of Anjou and other Latin leaders. There were long preliminaries at Constantinople, and at the council the Greek delegates made all the necessary concessions, including the concession on the Filioque issue (see creed), and reunion was proclaimed. The reunion, however, was unpopular in the East and ignored in the West and was officially denounced by Michael's successor Andronicus II. The legislation of the council for church reform was well prepared, supported by statements submitted by the bishops for the pope. Emphasis was laid on abuses at the diocesan level (e.g., plural benefices, absentee clerics, and faulty elections). Perhaps the most important decrees were those that established the system whereby popes are elected by a conclave of cardinals, that set regulations for religious orders, and that granted special protections to the Dominicans and the Franciscans. The double procession of the Holy Spirit from the Father and the Son ( Filioque ) was formally defined. St. Bonaventure died at the council, and St. Thomas Aquinas died on his way there.