Thank you,
davem, for a wonderful association and for the wonderful picture of the Lewis chessmen. (I'm thankful you provided the quotation as the link isn't working for me.) So, are we to understand this association as we read the story, or does it arrive after in contemplation?
I've seen the Lewis chessman--under class (plexiglass?) of course. They are marvels of exquisite workmanship; the faces remarkable for their individual expression. To my great regret now I did not at the time notice the attributes of the shield biter or recall the tenuous link to The Hobbit (although I do remember thinking that the king rather appeared to have a rolling pin in his hands)--how much more I would have enjoyed them at the time had I had this knowledge of the berserkers then.
The fact that they were made in the latter part of the twelfth century (if the dating is accurate) suggests that the old legends and mythologies lived on in Norway at least well into what were Christianised centuries in England. (Can't say what the status was for Scotland.) We could probably do with more discussion here of how Tolkien incorporated allusions to the old Norse myths.
Now of course I'm off to look at several other 'bear' allusions and metaphors I've read.