How the people of Wales became Welsh
Britain in the early Middle Ages was very different to the country it is now. Rather than England, Scotland and Wales, the island consisted of numerous kingdoms, the fate and fortune of which fluctuated, as some kings gained lordship over others, some smaller kingdoms were swallowed by their larger neighbours and others fell to foreign invaders – including Vikings, in the ninth and tenth centuries.
http://www.heritagedaily.com/2017/10/people-wales-became-welsh/117020
