Dean Cain was born Dean George Tanaka on 31 July 1966, near Mount Clemens, Michigan, USA. His mother, actress Sharon Thomas, later married film director Christopher Cain, who adopted Dean and his brother; both boys took their stepfather's surname. Cain's biological father, Roger Tanaka, was an American serviceman of Japanese descent.
Cain is best known for playing Clark Kent and Superman in the television series Lois & Clark: The New Adventures of Superman (1993-1997), one of the most popular screen versions of the character. He went on to host the reality series Ripley's Believe It or Not! from 2000 to 2003, and has built a long career in film and television since.
Cain's connection to Wales comes through his mother's side of the family. He has described his own heritage as "mostly Welsh", alongside Irish, French-Canadian and, through his biological father, Japanese ancestry. He was born, raised and has spent his career entirely in the United States, so this is a matter of family descent rather than any personal connection to Wales.
Because no specific Welsh town or genealogical record for the Thomas family has been traced in reliable sources, Cain's Welsh connection should be understood as a general ancestral claim, made in his own words, rather than a documented link to a particular place in Wales.