Vikings were originally a Germanic people who did wear horned helmets in the Bronze Age, most likely for ceremonies related to their religion, but they gave them up later. As I said, they were originally a blonde, blue-eyed Germanic people who spoke a Germanic language and exhibited Germanic characteristics. As they spread across Europe and North Africa, particularly Europe, they incorporated other peoples by kidnapping locals to serve as wives or slaves and introduced those genes into their genome. However, they were initially a blonde, blue-eyed people.Neither horns nor language have anything to do with it.
The Vikings have a reputation for being fierce, but I think this has more to do with the climate in which they lived. Scandinavia, before the scientific age, was not a very conducive place for agriculture, and crops often failed. When this happened, some Vikings would take to their boats to search for food for their starving families. Also, the term "Viking" does not refer to a group of people but rather an activity. Vikings were raiders, and not all members of the Viking community were raiders.
Not true. Scandinavians still have ceremonies and parties where horned helmets might be worn for the fun of it.
Bull shit. What do you mean, "in which they lived"? Skåne, a major area of the Hanseatic League, is warmer than other Hanseaic nations such as Poland and Russia as well as Bulgaria, Belgium, etc. etc. etc.
Bull shit again. The name Viking comes from coastal sea points that offered shelter for anchoring their ships from rough seas thus giving them access to landing in order to replenish land stocks by bartering or by raiding. In other words, the term Viking most certainly does refer to a group of people.