Saint-Lô is a commune in north-western France, the capital of the Manche department in Normandy. Originally called Briovère (meaning "Bridge on the Vire River" in Gaulish), the town is built on and around ramparts. Originally it was a Gaul fortified settlement. The name "Saint-Lô", known since the 8th century, originates from Saint Laud, bishop of Coutances in 525–565, who had a residence here. According to tradition, the town received a new line of walls from Charlemagne in the early 9th century. It was sacked by the Vikings in 890. Later it flourished under the bishop Geffroy de Montbray, who built here a bridge and some mills.