It's interesting to see how much Christianity changed Scandinavia by suppressing parts of the culture, while at the same time so many symbols remains.
From the maypole to wishing my relatives God Jul. :)
But while we're talking about stealing things, I think this went in several directions, with lots of Norse views and figures being influenced by other religions, including Christianity. Vikings and their sagas aren't exactly ancient.
http://www.orkneyjar.com/history/maeshowe/maeshrunes.htm
[At almost 5000 years old Maeshowe definitely qualifies as ancient.]