John XIII, pope of the Catholic Church (b. 930)
Pope John XIII (Latin: Ioannes XIII; died 6 September 972) was the bishop of Rome and ruler of the Papal States from 1 October 965 to his death. His pontificate was caught up in the continuing conflict between the Holy Roman emperor, Otto I, and the Roman nobility. After long and arduous negotiations, he succeeded in arranging a Byzantine marriage for Otto II, in an effort to legitimize the Ottonian claim to imperial dignity. He also established church hierarchy in Poland and Bohemia.