Valhalla Rising... WTF is it about?

So, this is my first post on reddit, been following the site for a while now after being referred to it by my buddy.

I just had a conversation with a work associate about the film "Valhalla Rising", where neither of us could figure out exactly what is going on or why. We both conceded defeat and admitted that we were simply missing something.

I ask you, redditors, what the fuck did I miss? NOTHING happens in that movie at all. Figured this was the best place to get it cleared up.

Much appreciated. Some Canadian.