The article is interesting in everything except using the word "Viking" inappropriately. As someone who once was fascinated by the topic, I found that bit frustrating.

In 400 AD, germanic people were known by names like "Goths". The viking period started several hundred years later. The relationship of Germanic people with England was that three groups of them, the Angles, the Saxons and the Jutes, were settling there. A few hundred years later those people united in response to the Viking threat, then were conquered by the French duke of Normandy (which, interestingly, had nobility of Viking descent) and country became known as England and the people there became known as anglosaxon.

Just to give a sense of the timeline, stories of a legendary Celtic folk hero that was part of resisting the Germanic invasion later got carried to France in medieval times, mutated beyond belief, then reentered English as King Arthur.