Well, for the Viking era dogs were drawn on runestones/picturestones that depicted the sucessful afterlife in Valhalla. ( Tjängvide stone, around year 700-800 ) The fact that the norsemen wanted to bring their dogs into the afterlife with them says a lot about their bond. These dogs may of had 'jobs' but it would be wrong to say that they were not pets too, they were often buried with their masters when they died and they had personal names and were so important that they are mentioned in the sagas - so the view that they were companions as well as pets is clear. Dogs were the last animals alive on the failed greenland settlement ( the fate was tragic however ), so even when their masters had almost no food for themselves they fed their pets right until the end. So, generally the Norsemen loved their dogs as pets and saw them as more than just an animal who works for them.