Julian Cope presents Head Heritage

As far as I know Morris dancing is a relatively recent concept (c15th century), the name itself being a corruption of 'Moorish' in that the dances were originally an imitation of the dances of the Moors. Possibly hence the tradition (largely extinct) of blacking up.
Even if these dances were danced at festivals with possible pagan ancestry, it seems unlikely that the dances themselves have any pre-historic origin.
In any case, by the 19th century, Morris was almost entirely extinct so most modern dances will be fairly recent elaborations on a small number of dances that had survived.
I've just read the wikipedia entry and it does seem to agree in the most part with what I have read in the past.
I would like to learn more about these Sardinian dances/costumes as, skimming the surface, there seems to be a widely held belief that these do have prehistoric origins...