Era
Vol. 1: A seculo VI usque ad 803
Series
Date
Circa 607
Regestum

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).

Source
Paul the Deacon, History of the Lombards, book 4, chap. 33. Original autograph is lost, numerous copies from 8th century onwards exist (cf. Bethmann's and Waitz's edition referenced below). FIM edition is based on the following manuscript:
B = Cividale del Friuli, Museo Archeologico Nazionale, Archivi e Biblioteca, ms. XXVIII, fol. 48r-v; copy from the second quarter of the 9th century; the manuscript is digitized and available online for consultation here.
Previous Editions
Ludwig Konrad Bethmann and Georg Waitz (eds.), Pauli Historia Langobardorum, Monumenta Germaniae historica, Scriptores rerum Germanicarum in usum scholarum separatim editi 48 (Hannover 1878), pp. 159-60.
FIM Edition
Diplomatic edition based on B.
Transcription

His diebus defuncto Severo patriarcha, ordinatur in loco eius Iohannes abbas patriarcha in Aquileia vetere, cum consensu regis et Gisulfi ducis. In Gradus quoque ordinatus est Romanis Candidianus antistis.a

Rursum mense novembrio et decembrio stellamb cometis apparuit.

Candidiano quoque defunctoc aput Grados ordinatur patriarcha Epiphanius, qui fuerat primicerius notariorum, ab episcopis qui erant sub Romanis.d
Et ex illo tempore coeperunt duo esse patriarche.e

Apparato critico

a) in Gradus add. al. man. in marg.     bsic: stella cum sig. abbr.     cex defunto corr.     d) primicerius notariorum add. al. man. in marg.     e) duo patriarche add. al. man. in marg.

Translation

In these days, after the death of the patriarch Severus, the abbot John was ordained in his place as patriarch in old Aquileia with the consent of the King and of Duke Gisulf. In Grado, Candidianus was also ordained bishop by the Romans.

A comet appeared again in the months of November and December. 

When Candidianus also died, Epiphanius, who had been chief of the secretaries, was ordained patriarch at Grado by the bishops who were under the Romans. And from that time there began to be two patriarchs.

[The translation, slightly modified by the editor, comes from Paul the Deacon, History of the Lombards, trans. William Dudley Foulke, ed. Edward Peters (Philadelphia 2003; 1st ed. 1907), p. 175.]

Medieval Recollections

1) The acts of the Synod of Mantua (see them here)

2) Carmen de Aquilegia numquam restauranda (see the poem here).

3) "Huic [Marcianus patriarcha, successor Severi patriarchae] successit Candidianus patriarcha in ipsa suprascripta metropoli Gradensi, sub cuius tempore per consensum Agiulfi regis Longobardorum Gisulfus dux per vim episcopum in Foroiulii ordinavit Iohannem abbatem, in quo tres episcopi consenserunt, Deo sibi contrario, et eum consecraverunt; tamen postea per epistolam domni Bonifacii pape urbis Rome sub eandem metropolim Gradensem se subiugaverunt." - Cronica de singulis patriarchis novae Aquileiae (ed. Monticolli, Cronache veneziane antichissime, vol. 1 (Rome 1890) pp. 9-10).

4) Cronicon Gradense repeats nearly verbatim the account of Cronica de singulis patriarchis novae Aquileiae (cf. ed. Monticolli, Cronache veneziane antichissime, vol. 1 (Rome 1890) p. 50).

5) John the Decon, Istoria Veneticorum, combines the accounts of Paul the Deacon's Historia Langobardorum with the narrative from the Cronica de singulis patriarchis novae Aquileiae: "His diebus defuncto Severo patriarcha, ordinatur in loco eius Iohannes abbas patriarcha in Aquilegia vetere cum consensu regis et Gisulfi ducis; in Gradus quoque ordinatus est a Romanis Marcianus antistis." [om.] "Rursum mense novembrii et decembrii stella commetis apparuit. Candidiano patriarcha quoque defuncto apud Gradus, qui Ecclesiam Gradensem rexerat annos quinque, ordinatur patriarcha Epyphanius, qui fuerat primicerius notariorum, ab episcopis qui erant sub Romanis, et ex ilio tempore ceperunt esse duo patriarche." (ed. Luigi Andrea Berto (Bologna 1999), pp. 70-72). 

It must be noted that patriarch Marcianus mentioned in these chronicles did not in fact succeed patriarch Sever. The real Marcianus was a 6th-century bishop, probably of Oderzo, mentioned in an epigraph from St. Euphemia's cathedral in Grado (HIC REQVIESCIT IN PACE CHRISTI SANCTAE MEMORIAE MARCIANVS EPISC[OPUS] QVI VIXIT IN EPISCOPATO ANNOS XLIIII ET PEREGRINATVS EST PRO CAVSA FIDEI ANNOS XI DEPOSITVS EST AVTEM IN HOC SEPVLCHRO VIII KAL MAIAS INDICT[IONE] VNDECIMA; see image 1 below), dead in 593 (= 11th indiction). From this epitaph, his name entered the catalogues of the patriarchs of Grado as an error and the 11th indiction was interpreted as 607.

Thus, since Paul the Deacon's account is the oldest and confirmed by the acts of the Synod of Mantua from 827, the chronology of the patriarchs of Aquileia and Grado should be reconstructed based on the account penned in the History of the Lombards.

Selected Bibliography
Paolo Cammarosano, "Aquileia e Grado nell’alto medioevo, Antichità altoadriatiche 36: Aquileia e l’Arco Adriatico (Udine 1990), pp. 129-55.
Giorgio Fedalto, Aquileia: Una chiesa due patriarcati, Scrittori della Chiesa di Aquileia 1 (Città Nuova 1999).
Editor's Notes

The event marks the official split of the Ecclesiastical province of Aquileia into two patriarchal sees. At first, the Lombard patriarch of Aquileia exercised spiritual jurisdiction over the Lombard territories of Venetia et Histria; the Roman patriarch of Grado retaining the jurisdiction over Byzantine, imperial territories, including Istria and the Venetian lagoon. The competition for the jurisdiction over Istrian bishoprics began with the Lombard conquest of Istria (see the sources here) and gained new ground with the Carolingian annexation of the peninsula in 788 (see the sources here). See more on the conflict between Aquileia and Grado here.

How to Cite
First citation: Josip Banic (ed.), Fontes Istrie medievalis, vol. 1: A seculo VI usque ad 803, doc. 607_HL, fontesistrie.eu/607_HL (last access: date).
Subsequent citations: FIM, 1: doc. 607_HL.
Facsimile
Image
Image Source and Info

The image of the manuscript comes from the project I libri dei patriarchi, available freely online on the following link: https://www.librideipatriarchi.it/

The editor has subsequently marked the image with a red vertical line simply to denote the part of the manuscript that is hereby edited.

All images remain under the copyright of their respective institutions.

The image of the epitaph comes from Giorgio Arnosti, "Il sinodo tricapitolino di Marano (aa.590-591)," available online here.