Emperor Justinian I issues a pragmatic sanction regulating the administration of the newly conquered Italy (the so-called sanctio pragmatica pro petitione Vigilii or epitome constitutionum Iustiniani de reformanda Italia).
Pope Pelagius II confirms Grado as the new metropolitan see of the ecclesiastical province of Venetia et Histria; 11th-century forgery.
King Charlemagne bestows to the Church of Aquileia the right to canonical election of their patriarchs (that nonetheless requires royal confirmation) and exempts it from public taxes such as the tithes, the grazing fees for livestock sent to graze in Istria, and war taxes (lodgings and provisions for the army) unless the royal military is forced to pass through Friuli and the Treviso region.
King Charlemagne confirms the possessions of the Church of Aquileia and grants it immunities.
Emperor Charlemagne subordinates six episcopal sees to the Church of Aquileia, badly damaged by the incursions of the pagans; late-10th-century forgery.
Emperor Charlemagne bestows immunities upon the Church of Grado due to the special services and merits of its incumbent Patriarch Fortunatus II.
Emperor Charlemagne exempts the four ships of Fortunatus II, "the patriarch of the Venetians and Istrians," from all the tolls.
The Plea of Rižana (Placitum Rizianense): The representatives of Istrian towns and cities present their grievances to counts Aio and Cadulus, the envoys of the Roman emperor Charlesmagne, in an official placitum held by the river Rižana in the district of Koper.
Emperor Louis the Pious promises to Patriarch Fortunatus II and to all the Istrians that their right to elect their own patriarchs, bishops, abbots, tribunes, and other officials will be respected and that the rulings of the judicial assembly (placitum) held by Rižana will be upheld.
Emperor Lothair I confirms the immunities enjoyed by the Church of Aquileia and its right to canonically elect their patriarchs.
The first pact between the Western Roman Empire, represented by Emperor Lothair I, and the Duchy of Venice, represented by Doge Pietro Tradonico, sanctioning mutual aid in campaigns against the Slavs and defining the rights over the use of land as well as the modalities of justice administration. This is the first "international" treaty in which Venice partook as an autonomous polity, independent of the Byzantine Empire.
Emperor Louis II assumes under his protection the monastery of St. Michael in Diliano and its abbot Felmo, bestowing upon the monastery immunities and the right of free election of its abbots.
Emperor Louis II confirms the charter of Lothair I to the Patriarchate of Aquileia regarding the dispute with the Patriarchate of Grado that was settled at the Synod of Mantua in 827: the patriarchs of Aquileia are to enjoy the metropolitan jurisdiction over all the Istrian bishoprics.
Emperor Louis II confirms to St. Michael's monastery in Diliano and abbot Felmo the right to have two lay advocates - the brothers Petronasius and Talasius - to defend their rights.
King Berengar I donates two forts, the Vermes (Beram in Istria ?), to the Bishopric of Trieste (10th- or 11th-century forgery).
King Hugo donates Sipar, Umag, and Monfalcone to Radald, the bishop of Trieste, and places the Bishopric of Trieste under his royal protection; a forged charter.
Hugh of Arles and his son Lothair II, kings of Italy, donate Muggia to the Patriarchate of Aquileia.
Emperor Otto I donates Izola in Istria to the Venetian Vitale Candiano.
Emperor Otto II gifts large estates on both sides of the Alps, including the Province of Istria, to his wife Theophanu as a dowry.
Otto II, Emperor of the Holy Roman Empire, donates properties in the March of Carniola to Abraham, the bishop of Freising.
Otto II, Emperor of the Holy Roman Empire, donates properties in the March of Carniola to Abraham, the bishop of Freising.
Emperor Otto II confirms the purchase of Izola, sold by Vitale Candiano to Patriarch Rodoald of Aquileia.
Emperor Otto II confirms the jurisdictions of the bishops of Poreč and grants them immunities.
Emperor Otto III confirms the donation of six bishoprics to the Patriarchate of Aquileia issued by Charlemagne and donates three abbeys to the same Church.
Pope Sergius IV confirms the jurisdictions of the bishops of Poreč over Rovinj, Dvigrad, and Bale that were disputed by the Aquileian patriarch John.