Norwegians tend to be pretty humble people, and they don't often celebrate their own accomplishments. I think a birthday is a good way to celebrate friends and family, especially in a culture that doesn't emphasize individuality as much as we do back home. Also, everyone loves the chance to eat some yummy treats!
Though much of Norwegian life is connected to the environment, birthday celebrations relate more to the communities you make for yourself rather than the environment that surrounds you. People celebrate with their families, friends, collegues, teammates or anyone else they want to share their special day with. That being said, since Norwegians love the outdoors so much, many people chose to celebrate their birthday outside, maybe on a ski tour or over a fire pit.
