Short answers, pulled from the story.
The Norsemen were a Germanic cultural group of the Early Middle Ages who originated among speakers of Old Norse in Scandinavia. During the late eighth century they began a large-scale expansion in all directions, launching the Viking Age. Modern descendants of Norsemen are called Scandinavians.
The word Norseman first appears in English in Walter Scott's 1817 work Harold the Dauntless. The adjective "norse" had been borrowed into English from Dutch during the sixteenth century, originally meaning "Norwegian," and had expanded by Scott's time to cover all of ancient and medieval Scandinavia.
The Old Frankish word Nortmann, meaning Northman, was Latinised as Normannus and entered Old French as Normands, producing both the Normans and the name Normandy, which Norsemen settled in the tenth century. Archaeologists and historians believe Norse settlements in Eastern Slavic lands also formed the basis for the names Russia and Belarus, possibly derived from the Swedish coastal area of Roslagen.
Germans called them Ascomanni (ashmen), Gaels called them Lochlanach, and Anglo-Saxons used Dene (Danes). Dubliners called Norse settlers Ostmen or East-people, preserving the name in the Dublin district of Oxmanstown. Slavs, Arabs, and Byzantines knew them as the Rus or Rhos, and the Byzantines also called them Varangians, meaning sworn men.
Leif Erikson, an Icelandic explorer born around 970 and living to around 1020, is widely credited as the first European to have set foot on continental North America. Freydis Eiriksdottir, born around 970, was also an explorer and early colonist of Vinland, the Norse name for North America.
Those who plundered Britain lived in what is now Denmark, Scania, the western coast of Sweden and Norway, the Swedish Baltic coast, and the island of Gotland. The southernmost Norse communities lived no further north than Newcastle upon Tyne, and they traveled to Britain more from the east than from the north.