"Pre-roman peoples more sophisticated than first thought" seems to be a perennial headline for prehistoric archaeology in Europe. Certainly research has overturned the impression of the northern Europeans as cannibals and cavemen, but the public image of the pre-Roman era could be thirty or more years out of date compared to current archaeology. It's something I want to blog about, but not right now as the findings are upsetting some people.
One possible reason is that so many modern societies in Europe equate themselves with the Romans as being civilised. Modern archaeology arguably started when the Danes started thinking seriously about their prehistory. They had a past which wasn't in the classical histories so they needed a past which could sit alongside the classical histories of southern Europe. I suppose if you subconsciously equate Rome with high culture, and the public architecture of 19th century Europe is often replete with classical columns and fixtures, then the idea of social complexity before the Roman period is almost unthinkable.