North Germanic peoples
Vikings were also active in Francia. Some of these Vikings would sail through the Strait of Gibraltar and pillage the coasts of the Mediterranean Sea. In the early 10th century, a group of Vikings under the leadership of Rollo settled in Rouen, France, and established the Duchy of Normandy. The descendants of these Vikings, known as the "Normans", would in the 11th century conquer England, Southern Italy, and North Africa, and play a leading role in launching the Crusades. Sub-groups of the Normans include Anglo-Normans, Scoto-Normans, Cambro-Normans, Hiberno-Normans and Italo-Normans.
Vikings
As early as 839, when Swedish emissaries are first known to have visited Byzantium, Scandinavians served as mercenaries in the service of the Byzantine Empire. In the late 10th century, a new unit of the imperial bodyguard formed. Traditionally containing large numbers of Scandinavians, it was known as the Varangian Guard. The word "Varangian" may have originated in Old Norse, but in Slavic and Greek it could refer either to Scandinavians or Franks. The most eminent Scandinavian to serve in the Varangian Guard was Harald Hardrada, who subsequently established himself as king of Norway (1047–1066).