Cimiez remained a heap of ruins, but Nice was re-peopled and rebuilt, not, however, near the port, but on the height of Le Château. The population of this part of the old province revolted against the Franks; and Nice entered into a league with Genoa and other important towns on the Italian Riviera. In 741, however, the province again returned under the domination of the Franks, and it was governed by counts appointed by the sovereign, who resided at Nice in the castle. Here, hard by on the rock, was the cathedral, and down the north-west slope, that was least precipitous, were lodged the private houses. In 775 the abbey of S. Pontius was founded by Siagrius, Bishop of Nice, and Charlemagne, who is supposed to have been his uncle, gave the funds for the building and endowment. This abbey was erected on the rock on which, according to tradition, S. Pontius had suffered martyrdom by decapitation.
Profiting by the break-up of the Carolingian dynasty, in 880, Boso, whose sister was married to Charles the Bald, seized on that part of Burgundy which is on this side the Jura, and along with Provence constituted a kingdom, with himself at its head.
In 889 the devastations committed by the Saracens extended along the coast, and one town after another was sacked and burnt by them. These ravages continued till 973, when William, Count of Provence, and Gibelin Grimaldi freed the land from this plague. The Saracens had a fortress at Saint Hospice, a curious spur which strikes out from the peninsula of Cap Ferrat, whence they had harassed the neighbourhood of Nice, but had been unable to storm the fortified town on the rock.