Carolus Magnus (Francogallice et Anglice Charlemagne; Theodisce Karl der Große, Italice Carlo Magno, Croatice Karlo Veliki) (742–814), filius regis Pippini Brevis et Bertradae Lauduni reginae Francicae, fuit Rex Francorum a anno 768 et Imperator Romanorum a anno 800 ad mortem.
Pope Adrian I writes to Charlemagne, the King of the Franks and the Lombards, beseeching him to direct Duke Marcarius of Friuli to help reinstate the Istrian bishop Maurice – whose eyes have been gouged out by “the most abominable Greeks” – to his bishopric.
Narrative sources on the events of 788 that resulted, among a variety of other things, with Istria being incorporated into the Frankish kingdom.
King Charlemagne writes to his wife Fastrada, informing her, among other things, of their military successes against the Avars, including the achievements of his “duke of Istria”. This is the first documented mention of a Carolingian official in Istria, officially marking the beginning of a new era of the peninsula’s history.
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.
A poem composed in response to the Synod of Mantua (6th of June, 827), arguing that Aquileia, the old metropolitan see of the ecclesiastical province Venetia et Histria, was so thoroughly destroyed by barbarians (Attila, the Avars, Lombards and Goths) that it was never rebuilt; thus, the metropolitan see transferred to "the Venetians" and Aquileia was demoted to a status of a mere parish.
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.