John XXII, 1244–1334, pope (1316–34), a Frenchman (b. Cahors) named Jacques Duèse; successor of Clement V. Formerly, he was often called John XXI. He reigned at Avignon. John was celebrated as a canon lawyer under Boniface VIII, whom he supported. After the death of Clement there was a period of more than two years before the conclave could agree. Before John's election a contest had begun for the title of Holy Roman Emperor between Louis IV of Bavaria and his rival, Frederick of Austria. John was neutral at first; then in 1323, when Louis had won and became Holy Roman emperor, pope and emperor began a serious quarrel. This was partly provoked by John's extreme claims of authority over the empire and partly by Louis's support of the spiritual Franciscans, whom John XXII condemned for their insistence on evangelical poverty. Louis was assisted by Marsilius of Padua, who in 1324 published his exposition of his theories Defensor pacis, and later by William of Ockham. The emperor invaded Italy and set up (1328) as an antipope Pietro Rainalducci (as Nicholas V). The project was a fiasco, but Louis silenced the papal claims. In John's last years he advanced a theory concerning the vision of God in heaven or the beatific vision; the novelty he proposed (that this vision will begin only after the Last Judgment) was widely denied and scorned by theologians, and John subsequently modified it. He was an excellent administrator and did much efficient reorganizing. He was succeeded by Benedict XII.