The Feast of Corpus Christi originated in 1246 when Robert de Torote, bishop of Liège, ordered the festival celebrated in his diocese. He was persuaded to initiate the feast by St. Juliana, prioress of Mont Cornillon near Liège (1222–58), who had experienced a vision. It did not spread until 1261, when Jacques Pantaléon, formerly Archdeacon of Liège, became pope as Urban IV. In 1264 he ordered the whole church to observe the feast. Urban’s order was confirmed by Pope Clement V at the Council of Vienne in 1311–12.