None of the Welsh actors & actresses, that I can think of, are swarthy at all. But then, these are the only Welsh people whom I know what they look like.
Richard Burton, Anthony Hopkins, Ray Milland, Ioan Gruffudd,Hugh Griffths, Stanley Baker, Glynis Johns, Catherine Zeta-Jones,Dawn French, Sian Phillips, for example.
Tom Jones is a little swarthy.
;)
Think Tom Jones, John Rhys-Davies, Zeta Jones appears Mediterranean compared to most British.
Here are some interesting articles for the curious:
http://news.bbc.co.uk/2/hi/south_asia/4328733.stm
http://www.sanskritimagazine.com/indian-religions/hinduism/the-celtic-vedic-connection/