You might like Robo Geisha and Tokyo Gore police even more, then.
Well the context has to be somewhat interesting to me. Seems like those are somekind of Japan stuff which I'm not too greatly into. Especially if they play with symbolism and some old mythologies etc like in Valhalla Rising, I'm most likely getting nothing out of them.
My thoughts:
Valhalla Rising requires some knowledge of Scandinavian mythology and symbolism. When I watched the movie for second time, to me it's about how Christianity replaces the old Gods and human gets driven further away from the nature. The main character (Mads Mikkelsen) also refers to Odin (one eye just like Oden has according to Edda). As so he also represents Scandinavian mythology as a whole (inprisonment and finally just forced to deal with Christianity).
The new land they enter is ofc America and the hostile people are indians (see the way they bury the dead, it's the old indian cemetary way.) Collecting rocks and piling them up is old tradition here in Northern Europe and I think it refers to the rock piles found in North America (different place than the longhouses where vikings are assumed to land America).
I bet there is still a lot stuff I'm not able to get a hold on, but these things I think I've understood correctly