Richard Dafydd Vivian Llewellyn Lloyd (8 December 1906 ? 30 November 1983), better known by his pen name Richard Llewellyn, was a Welsh novelist.

Several of his novels dealt with a Welsh theme, the best-known being How Green Was My Valley (1939), which won international acclaim and was made into a classic Hollywood film. It immortalised the way of life of the South Wales Valleys coal mining communities, where Llewellyn spent a small amount of time with his grandfather.

His 1943 novel, None but the Lonely Heart, was adapted into the film of the same name in 1944. The film was directed by Clifford Odets and starred Cary Grant, Ethel Barrymore, Barry Fitzgerald, June Duprez, Jane Wyatt, George Coulouris, and Dan Duryea. The film won the Academy Award for Best Supporting Actress (Ethel Barrymore) and was nominated for Best Actor in a Leading Role (Cary Grant), Best Film Editing and Best Music, Scoring of a Dramatic or Comedy Picture (Hanns Eisler and Constantin Bakaleinikoff).

There is no entry about the novel available on Wikipedia at this time, but here is a link to the film entry.