Norsemen, name given to the Scandinavian Vikings who raided and settled on the coasts of the European continent in the 9th and 10th cent. They are also referred to as Northmen or Normans. Recent research indicates that Norse raids of Western Europe may have been known in the early Middle Ages. Among the causes of the great influx (9th cent.) of Norsemen to the coasts of NW Germany, the Low Countries, France, and Spain were lust for wealth and power, search for adventure, and the attempt of King Harold I of Norway to subjugate the independent nobles of his land, thereby forcing them to look to foreign conquests. The impact of the Norse invasions was particularly lasting in N France. The invaders, whose major raids began c.843, sailed up the French rivers, particularly the Seine, and repeatedly attacked, looted, and burned such cities as Rouen and Paris. Their actions threatened to plunge France back into the barbarism from which it was just emerging. The Norsemen gradually established settlements, generally at the river mouths; thus they constantly threatened to renew their river raids, and they ruined French commerce and navigation. In 911, Rollo, one of their leaders, was invested by King Charles III (Charles the Simple) with the duchy of Normandy, originally the territory around Rouen. Rollo's successors considerably expanded their territory and were only nominal vassals of the French kings. The Norsemen accepted Christianity, adopted French law and speech, and continued in history under the name of Normans. The name of Normandy itself and several Norman place names are survivals of the Norse period. The Norsemen did not differ essentially from the other Vikings, who were known as Danes in England and as Varangians in Russia.
See T. D. Kendrick, A History of the Vikings (1930, repr. 1968); E. C. Oxenstierna, The Norsemen (tr. 1965) and The World of the Norsemen (tr. 1968).