(Jan. 898–Jan. 900)
On the death of Theodore II the partisans of Stephen VI, sworn foes of his posthumously condemned victim Formosus, seized the initiative and elected Sergius, bishop of Caere (Cerveteri), as pope. Although he took possession of the Lateran, the Formosan party, with help from Lambert of Spoleto, king of Italy since 891, whom Formosus had crowned emperor on 30 Apr. 892, forcibly expelled him and elected John, a Benedictine monk born at Tivoli, whom Formosus had ordained. The scanty records of this turbulent period have left the course of events and their dates obscure.
With cooperation from the emperor, who controlled Rome and most of Italy, John at once continued Theodore's policy of restoring order in the confused situation arising out of Stephen VI's trial of the dead Formosus and the ensuing violent clashes between Formosans and anti-Formosans. He convened a synod at Ravenna, attended also by bishops from north Italy, which annulled the ‘cadaver synod's’ sentence on Formosus and burned its acts; those who had taken part in it were pardoned after pleading that they had done so under duress; only Sergius and five close associates were deposed and placed under a ban. The trial of dead persons was prohibited in future. Formosus' ordinations were recognized as valid, as was his anointing of Lambert as emperor; but his anointing of Arnulf, king of the East Franks, as emperor was rejected as ‘barbaric’ and as having been extracted from him by force. The prohibition of the translation of bishops was confirmed, the case of Formosus being treated as exceptional. To prevent disorders at papal elections it was decreed (reviving the constitution of Emperor Lothair I of 824) that in future, while the pope should be elected by bishops and clergy on the request of the senate and people, his consecration could only take place in the presence of imperial emissaries.
The synod sought to ensure the support of the Spoletan royal house for the Roman church. In particular, it provided every Roman, clerical or lay, with the right to appeal to the emperor and restored his supreme jurisdiction. In return Lambert renewed the ancient privileges of the holy see and guaranteed its territorial possessions, his own position as overlord being ensured. The bright prospects which these agreements seemed to hold out were cruelly dashed when the young emperor was unexpectedly killed in a hunting accident on 15 Oct. 898.
An important letter of John's indicates that he either prepared or at any rate ratified the reconciliation in the Byzantine church of the schismatic followers of Patriarch Ignatius (d. 877) with Patriarch Antony Cauleas (893–901). In it the pope assured Metropolitan Stylianos, leader of the Ignatian faction, that Rome fully recognized ‘Ignatius, Photius [i.e. at least his second patriarchate from 877–86], Stephen, and Antony’, and exhorted him to live in communion with clergy ordained by them. In Moravia, where the arrangements made by Stephen V had collapsed, John tried to restore order by sending an archbishop and two legates, only to be reproached by the bishops of Bavaria for intruding. But in 906 the Moravian state was to fall in pieces before the Magyar invaders. In France he restored Argrinus of Langres, deposed by Stephen VI, to his see. He is recorded as having confirmed the privileges of the great abbey of Monte Cassino, province of Frosinone, founded by St Benedict (c. 480–c. 550) in 529.