Environmental Changes
The Romans introduced a number of species to Britain, including possibly the now rare Roman nettle (Urtica pilulifera), said to have been used by soldiers to warm their arms and legs, and the edible snail Helix pomatia. There is also some evidence they may have introduced rabbits, but of the smaller southern mediterranean type. The European rabbit (Oryctolagus cuniculus) prevalent in modern Britain is assumed to have been introduced from the continent after the Norman invasion of 1066.
Read more about this topic: Roman Britain