The siege lasted until the spring of 774 when Charlemagne visited the pope in Rome. There he confirmed his father's grants of land, with some later chronicles falsely claiming that he also expanded them, granting Tuscany, Emilia, Venice and Corsica. The pope granted him the title "patrician". He then returned to Pavia, where the Lombards were on the verge of surrendering. In return for their lives, the Lombards surrendered and opened the gates in early summer. Desiderius was sent to the abbey of Corbie, and his son Adelchis died in Constantinople, a patrician. Charles, unusually, had himself crowned with the Iron Crown and made the magnates of Lombardy pay homage to him at Pavia. Only Duke Arechis II of Benevento refused to submit and proclaimed independence. Charlemagne was then master of Italy as king of the Lombards. He left Italy with a garrison in Pavia and a few Frankish counts in place the same year.