In 753, Grifo went to Italy to join the King of the Lombards, Aistulf, the most powerful opponent of his half-brother, the King of the Franks, Pepin the Short, but he was killed at Saint-Jean-de-Maurienne by the men of Pepin.
The oldest possessions of the Counts of Savoy were the counties of Maurienne, Savoy proper (the district between Arc, Isère, and the middle course of the Rhone), and Belley, with Bugey as its chief town.