This video says about itself:
From Environment and History, Volume 20, Number 3:
The Grass Snake and the Basilisk: From Pre-Christian Protective House God to the Antichrist
The grass snake owes its far northern distribution in Europe to the production and hoarding of dung from stock breeding. Dung heaps appear to be perfect breeding sites that surpass ‘natural’ reproduction sites in quality. Here we point out that the grass snake‘s dependency on manure goes back to Neolithic times and that it had a reciprocal cultural effect.
Moreover, the positive influence of humans on the species not only resulted from physical opportunities offered by agriculture, but also from the fact that grass snakes were considered to be chthonic deities not to be harmed.
The conversion of Europe to Christianity, however, marked the turning of the cultural tide for the species. From being a divine creature originally, the grass snake evolved into the number one symbol of the Anti-Christ: the basilisk.
In spite of the subsequent witch-hunt motivated by Christian belief, the overall historical human influence on the species was certainly not detrimental as regarded geographical distribution opportunities. This historical perspective on grass snake-human relationships adds to the discussion of whether nature conservation is better served by a strategy of land sparing or of land sharing.
It also makes clear not only that co-dependency of species is a matter of mutual biophysical advantages but that metaphysical considerations may also play a role. In this case it leads to the conclusion that bringing back the grass snake into our direct everyday surroundings is both favourable to the grass snake and reinstates the species in our own cultural environment.