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.
Viking Age
In Scandinavia, the Viking age is considered to have ended with the establishment of royal authority in the Scandinavian countries and the establishment of Christianity as the dominant religion. The date is usually put somewhere in the early 11th century in all three Scandinavian countries. The end of the Viking era in Norway is marked by the Battle of Stiklestad in 1030. Although Olafr Haraldsson's (later known as Olav the Holy) army lost the battle, Christianity spread, partly on the strength of rumours of miraculous signs after his death. Norwegians would no longer be called Vikings. In Sweden, the reign of king Olov Skötkonung ( 995–1020) is considered to be the transition from the Viking age to the Middle Ages, because he was the first Christian king of the Swedes, and he is associated with a growing influence of the church in what is today southwestern and central Sweden.