Also, if you are interested I have a few older posts (http://baleanoptera.livejournal.com/tag/kittelsen) (even older than this one. ;D) that shows more of Kittelsen's fairytale art.
The Norwegian fairytales were collected and published, inspired by the works of the Brothers Grimm, and Kittelsen was one of the artists who illustrated them.

(another famous illustrator was Erik Werenskiold - but personally he has never touched me the way Kittelsen has.)