ThePatriarchate of Old Aquileia was created in 607, during theSchism of the Three Chapters in thePatriarchate of Aquileia. It was centered in the oldAquileia, that was held by theLombards who wereArians, while the rivalPatriarchate of New Aquileia inGrado was allied with theByzantine Empire.[1]
The bishops under the patriarch of Aquileia had split with Rome when they refused to condemn theologians who had been condemned by the rest of the Church. After theLombard invasion of Northern Italy they had fled to theisland of Grado, then under control of theByzantines, although for years they maintained the schism. In 606 the newly elected bishop reconciled with Rome.
Many mainland bishops, whose dioceses were underLombard control were unhappy with the reconciliation. These dissidents fled to mainland Aquileia and under Lombard protection elected a John as a rival patriarch who maintained the schism. There were now two patriarchates in northern Italy,Aquileia in Grado and Old-Aquileia.
Thus, the schism deepened now along political Lombard-Roman lines.
TheIrish missionaryColumbanus, who was ministering to the Lombards inBobbio was involved in the first attempt to resolve this division through mediation between 612 and 615. He was persuaded byAgilulf,King of theLombards, to address a letter on the schism toBoniface IV. He tells the pope that he is suspect of heresy for accepting theFifth Ecumenical Council (the Second Council ofConstantinople in 553), and exhorts him to summon a council and prove his orthodoxy.[2]
Edward Gibbon claims thatPope Honorius I reconciled the Patriarch to Rome in 638, although this did not last.[3]
As the schism lost its vigour, the Lombards started to renounce Arianism and become Catholics. The bishops of Old-Aquileia formally ended the schism at theSynod of Pavia in 698. After Old-Aquileia reconciled with Rome, Pope Gregory II granted thepallium to Patriarch Serenus (715-730) of Aquileia in 723.
The Patriarch of Old-Aquileia became simply the Patriarch of Aquileia, although the title was often claimed by thePatriarch of Grado - who was now more commonly known as simply the Patriarch of Grado.
Both sees were later suppressed.
Holders of the office who were recorded are: