Pope Pelagius II writes to Helias, the patriarch of Aquileia, and all the bishops of Istria, the province whose prelates still persevered in their refusal to condemn the three chapters denounced by the Fifth Ecumenical Council (Constantinople II) of 553, urging them to desist from their schismatic ways and return to the embrace of the Catholic Church.
Pope Gregory I writes to Severus, the patriarch of Aquileia, requesting on behalf of the emperor (Maurice) that he come to Rome with his clergy and be judged on a synod (for his unwillingness to condemn the Three Chapters and his perseverance in supporting the schism).
Emperor Maurice writes to Pope Gregory I, urging him not to treat violently the schismatic bishops of the ecclesiastical province of Aquileia (the "Istrian bishops") and not to compel them to journey to Rome.
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.
Pope Gregory I writes to Maxim, the bishop of Salona, on a variety of matters, including the latest advances of the Slavs and their recent incursions into Italy by way of Istria.