Pope Gregory I writes to Callinicus, the Exarch of Italy, regarding a variety of affairs, including the recent military victory over the Slavs and the return of the Church of Koper to the Catholic creed.
Istria as described in the chapters of Cosmography, penned by the anonymous Ravenna Cosmographer (Anonymus Ravennas), including the region's rendition on the famous Peutinger's Map (Tabula Peutingeriana).
Due to fair treatment and protection, the city of Koper, represented by a locopositus, scabini, the protector of the people (advocatus totius populi) and many others, freely promise an annual tribute of one hundred amphorae of wine to Venice, to be paid every year within ten days of the harvest, and protection to all Venetians.
Emperor Otto I donates Izola in Istria to the Venetian Vitale Candiano.
Emperor Otto II confirms the purchase of Izola, sold by Vitale Candiano to Patriarch Rodoald of Aquileia.
Upon the petition of the citizens of Koper, who suffered due to their allegiance to the Empire, Emperor Conrad II confirms their possessions, their customary law, immunities, and the freedom to trade in the Empire.
Answering the pleas of Aquileian Patriarch Berthold, Emperor Frederick II proclaims and ratifies the verdict of the imperial princes gathered at the Diet of Ravenna, confirming the secular rights and prerogatives of Aquileian patriarchs and forbidding the election of rectors and the exercise of regalian rights to the subjected urban communities, especially to the Istrian cities of Koper, Poreč, and Pula.
Emperor Frederick II confirms the treaty signed between Aquileian Patriarch Berthold V and the Commune of Koper.
Count Maynard III of Gorizia promulgates an arbitrational sentence in a dispute between Aquileian Patriarch Berthold V and the Commune of Koper regarding the elections of podestàs, the prerogatives of the appointed gastalds and the administration of criminal justice, fines above a hundred bezants and the patriarch’s right to emend the local statute.
Roman king Conrad IV orders Berthold, the margrave of Vohburg-Hohenburg, to explain to the podestà of Koper, Andrea Zeno, and to the Capodistrians under his authority, how the Margraviate of Istria is an imperial land bestowed unto the late Aquileian Patriarch Berthold V of Andechs by the king’s father (Emperor Frederick II), but now, with the patriarch’s death, the Empire can again freely dispose with the Margraviate and therefore, the citizens of Koper should not swear any fealty to the newly elected Aquileian Patriarch Gregory of Montelongo, but persevere in their allegiance to the Empire.
Roman King Conrad IV accords privileges of the free elections of podestàs to the Commune of Koper, as long as they are elected from among those faithful to the Empire.
The Commune of Koper authorizes ten of its citizens to represent the Commune in reaching a peace treaty between the patriarch of Aquileia and the count of Gorizia.
A peace treaty is reached between Aquileian Patriarch Raymond della Torre and his advocate Albert, Count of Gorizia, together with his allies which included the Commune of Koper and Piran.
With the help of Fulcher, the bishop of Concordia, a peace treaty is reached, signed between Venice on the one side and the Patriarchate of Aquileia, the count of Gorizia, and the Commune of Trieste on the other, ending the war that had begun in 1283.
Venice signs a peace treaty with the patriarch of Aquileia, Count Albert I of Gorizia, and the Commune of Trieste, ending their final conflict and restoring amicable relations as defined by their previous pacts; Venice retains the jurisdictions over the subjected communities in Istria with the exception of Muggia, Buje, and Dvigrad; the settlement of the dispute over the jurisdictions in Istria between Venice and the Patriarchate of Aquileia is entrusted to Pope Nicholas IV.
Doge Antonio Venier asks Margrave Domnius of Castello to compensate the mussolati (traders) from Završje who were robbed of their wine in the district of Venetian Koper by his subjects from Petrapilosa. He also asks Domnius to exemplarily punish his subjects who committed this robbery.
The Venetian Senate debates the future of the newly conquered strongholds in Istria: Oprtalj, Petrapilosa and Buzet. First, the Venetian Senate decided to postpone deliberating on the fate of these three Istrian forts to another date and after lunch (P. 1); then, three days later, it votes on three proposals (P. 2–4), ultimately decreeing to accept the three communities into their dominion and keep their walls intact, authorizing the delegated rectors of Koper to appoint the citizens of Koper to serve as governors of these three places.
The Venetian Senate deliberates on the matter of the four recently annexed communinites in Istria and their unhappiness with the current regimen; the first proposal (P. 1), to modify the existing jurisdictional framework is rejected; the second proposal (P. 2) is accepted, changing absolutely nothing, but only advising the rectors of Koper to delegate literate and suitable persons to these posts.
The Council of Ten confirms the old privilege of the Commune of Koper and the original pact with Dvigrad by which the nobles of Koper elect among themselves the regularly rotating podestà of Dvigrad.