Rollo (c. 860–c. 932)

First Viking ruler and Duke of Normandy (although he never used the title). He founded the duchy of Normandy and established the dynasty of William (I) the Conqueror. The city of Rouen is named after him.

Rollo left Norway about 875 and marauded, sailing up the River Seine to Rouen. By the Treaty of St-Clair-sur-Epte (912), Charles III ‘the Simple’ (879–929) of West Francia granted Rollo the eastern part of Normandy as a buffer against other Scandinavians and recognized him as duke. By 924 Rollo had extended his control into central Normandy.