Severus, patriarcha Aquileiensis (587-606/7)

Following the death of Aquileian patriarch Helias, his successor, Patriarch Severus, together with three other bishops (including the bishop of Poreč, John) are imprisoned in Ravenna by the Byzantine exarch Smaragdus; in order to buy their freedom, the prelates agree to condemn the Three Chapters and reunite with Rome, a move that greatly angers other bishops in the ecclesiastical province of Aquileia. Finally, a synod is held in Marano (591) whereby Patriarch Severus is forced to formally acknowledge the error of his ways in supporting the condemnation of the Three Chapters (narrative accounts from Paul the Deacon's History of the Lombards).

Pope Gregory I writes to Severus, the patriarch of Aquileia, requesting on behalf of the emperor (Maurice) that he come to Rome with his clergy and be judged on a synod (for his unwillingness to condemn the Three Chapters and his perseverance in supporting the schism).

The bishops of the ecclesiastical province of Aquileia write to emperor Maurice, beseeching him not to allow their metropolitan, Archbishop Severus of Aquileia, who was forcefully taken to the pope in Rome, to be put on trial and judged by the adversaries of the Three Chapters, that is, the non-schismatic clergy; the bishops expound their viewpoints on the theological controversy, their fealty to the Ecumenical Council of Chalcedon, and why they refuse to denounce the so-called Three Chapters condemned by Emperor Justinian I and the Ecumenical Council of Constantinople in 553.

Following the death of Aquileian patriarch Severus, two new patriarchs are ordained: John, supported by the Lombards and with his seat in Aquileia; and Candidianus, supported by the Romans (Byzantines) with his seat in Grado - the definitive and official split of the patriarchate of Aquileia into two patriarchal sees (narrative account from Paul the Deacon's History of the Lombards).