This character/idea was developed after I had seen a very large, stocky guy sitting on an overcrowded train reading a book. He was so immersed in his book that he didn't seem to care that the environment around him was just crammed people. I think many people have been in that situation where a book, a movie or even a game has captured their mind and taken them to another world.
From this idea I thought it may be interesting to witness this situation as an outsider. For example if the large man were to act out his reactions on a crowded train, how would it affect the people around him. He could invade other peoples space without knowing or even knock-over someone standing by (being a large person it wouldn't be hard). At the characters destination/stop he could simply get up and walk away oblivious to the destruction he has left behind.
In regards to the actual drawing the reason he is a viking is that the actual man had a similar stature to what I related to as a viking and it helped to exaggerate the characters proportions and his jerk personality. Although it doesn't really fit the story setting so I will just say that I wanted to draw a powerful, mighty viking warrior overcome by the wondrous adventures of a book.