Fifty-five years ago when I was hanging around with English PhD students at university, they were all talking about being required to study Old Norse. So it was certainly recognized as important a long time ago. Then there is the part of eastern England which is called the Danelaw, because of the Danish influence there and its influence on the laws. Vikings also had an influence, but if the kind of legal scholarship that would have resulted in a name like “Danelaw” was present, it probably would have had more influence on structural things like grammar than the Vikings.
What often, well, usually, happens is, the educational requirements for degrees are tailored to the expertise of the teaching staff.