James Wilson, The evolution of British cattle and the fashioning of breeds…
“ Then, as the natives were pushed westward and northward, the Roman cattle they had been unable to secure were left behind to fend for themselves in the forests. For some centuries more, the country from which the Celts had been expelled was the arena of strife and war, by no means thickly populated, and exposed on the western border to continual rieving and raiding. And, so, when the Normans came in, they found the Roman cattle no longer quiet and uncomplaining animals of burden, but wild and ferocious beasts of chase. ”
