List of Bishops (c. 250-355) Archbishops (355-555) and Patriarchs (557-1045) of Aquileia, Patriarchs of Friule (1045-1077) and Patriarchs of Carniola (1077-1204), and then Patriarchs of Istria (1209-1752 secularized July 7, 1420).

• Hilarius of Panonia c. 276-285
• Chrysogonus I c. 286-295
• Chrysogonus II c. 295-308
• Theodore c. 308-319
• Agapitus c. 319-332
• Benedictus c. 332-?
• Fortunatianus c. 343-355
• Valerianus 369-388
• Chromatius 388-407
• Augustinus 407-434
• Adelphus 434-442
• Maximus I 442-444
• Januarius 444-447
• Secundus 451-452
• Nicetas 454-485
• Marcellianus 448-500
• Marcellinus 500-513
• Stephanus I 515-?
• Macedonius 539-?
• Paulinus I 557-569
• Probinus 569-570
• Elia (Patriarch of Aquileia) 571-586
• Severus 586-606
• Ioannes I 606 (opposite partiarch)
• Candidianus 606-612
• Epiphanius 612-613 (Patriach in Grado)
• Ciprianus 613-627 (patriarch in Grado)
• Marcianus (opposite patriarch) 623-628
• Fortunatus (opposite patriarch)628-663
• Primogenius 630-648 (Patriarch in Grado)
• Maximus II 649 (Patriarch in Grado)
• Felix (opposite Patriarch) 649-?
• Ioannes II (opposite Patriarch) 663-?
• Stephanus II 670-? (Patriarch in Grado)
• Agathon 679-680 679-?
• Ioannes III (opposite Patriarch) 680-?
• Christophoros (Patriarch in Grado) 685-?
• Petrus I 698-700
• Serenus 711-723
• Calixtus 726-734
• vacant or unknown 734-772
• Siguald 772-776
• Paulinus II 776-802
• Ursus I 802-811
• Manentius 811-833
• Andreas 834-844
• Venantius 850-?
• Theutmar 855-?
• Lupus I 855-?
• Valpert 875-899
• Fredericus I 901-922
• Leo 922-927
• Ursus II 928-931
• Lupus II 932-944
• Engelfred 944-963
• Rodoald 963-984
• Ioannes IV of Ravena 984-1017
• Poppo 1019-1045
• Eberhard 1045-1049
• Gotebald 1049-1063
• Ravengerius 1063-1068
• Sigeard of Beilstein 1068-1077
• Henry 1077-1084
• Frederick II of Moravia 1084-1085
• Ulrich I of Eppenstein 1086-1121
• Gerard I 1122-1128
• Pilgrim I of Ortenbourg 1130-1161
• Ulrich II of Treven 1161-1181
• Gottfried 1182-1194
• Pilgrim II 1195-1204
• Wolgfar of Leibrechtskirchen 1204-1218
• Berthold of Meran 1218-1251
• Gregorio of Montelongo 1251-1269
• Philipp I of Carinthia 1269-1273
• Raimondo of Torre 1273-1299
• Pietro II Gerra 1299-1301
• Ottobuono of Razzi 1302-1315
• Gaston of Torre 1316-1318
• Paganus of Torre 1319-1332
• Bertram of St. Genesius 1334-1350
• Nicolas of Luxemburg 1350-1358
• Ludovicus I of Torre 1359-1365
• Marquard of Randelle 1365-1381
• Philippe II of Alençon 1381-1387
• Jan V Sobieslaw of Moravia 1387-1394
• Antonio I Gaetani 1394-1402
• Antonio II Panciera 1402-1412
• Antonio III of Ponte 1409-1418 (1409-1412 opposite patriarch)
• Ludwig of Teck 1412-1439 (Ludovicus II or Ludwig II of Teck)
• Ludovicus III Scarampi-Mezzarota 1439-1465
• Marco I Barco 1465-1491
• Ermolaio I Barbaro 1491-1493
• Niccolo II Donati 1493-1497
• Domenico Grimani 1498-1517
• Marino Grimani 1517-1529
• Marco II Grimani 1529-1533
• Marino Grimani (2nd time) 1533-1545
• Giovanni VI Grimani 1545-1550
• Daniel I Barbaro 1550-1574
• Aloisio Giustiniani 1574-1585
• Giovanni VI Grimani (2nd time) 1585-1593
• Francesco Barbaro 1593-1616
• Ermolaio II Barbaro 1616-1622
• Antonio IV Grimani 1622-1628
• Agostino Gradenigo 1628-1629
• Marco III Gradenigo 1629-1656
• Hieronimo Gradenigo 1656-1658
• Giovanni VII Dolfino 1658-1699
• Dionisio Dolfino 1699-1734
• Daniel II Dolfino 1734-1752