Richard Rhys, who became the 9th Baron Dynevor in 1962, was a patron of the arts and he made a considerable contribution to cultural life, especially in Wales. A friend of his, the Welsh writer Emyr Humphreys, described him as “a left-over from another age of intellectual patronage. He was quite uncommercial.”

Richard Charles Uryan Rhys was born in 1935 and educated at Eton and Magdalene College, Cambridge, where he studied English. He left without taking a degree because he wanted to be an actor. He went to Dublin where a cousin, Edward Longford, was running the Gate Theatre. There he was given small parts.

In 1960 he founded the Merlyn Theatre, a touring group, and he arranged a tour of a play, Have a Cigarette by the Welsh writer Saunders Lewis, which provided Anthony Hopkins with his first professional part. He had just finished his course at the Welsh National School of Drama in Cardiff.

Later Dynevor worked with William Donaldson and brought Beyond the Fringe to London. He also produced several plays at the Theatre Royal in Stratford East. These included two plays by J. P. Donleavy — The Singular Man and Fairy Tales of New York — and a play by the novelist James Hanley, Say Nothing, which was performed there in 1962. There was also a musical, Loud Organs, by Gwyn Thomas, performed in Cardiff in 1969.

In 1959 Dynevor married Lucy, the daughter of Sir John Rothenstein, director of the Tate Gallery, who introduced him to wider artistic circles. In 1963 Dynevor made a film with Emyr Humphreys based on a long poem by R. S. Thomas, The Airy Tomb. It was shown on BBC Wales television and at the Venice Film Festival.

When his father died, in 1962, Dynevor inherited a large estate at Llandeilo in Carmarthenshire. This included a 12th-century castle overlooking the River Towy once painted by Turner, a large park with an ancient breed of white cattle, and Newton House, built in 1660.

The estate landed him with considerable death duties, and the responsibility brought to an end his work with the theatre in London. Nevertheless, he decided to develop Newton House into a centre for the arts and founded the Dynevor Festival, which ran for three years. In its first year, 1966, John Ogdon played Michael Tippett’s Second Piano Sonata. The Allegri String Quartet performed there, Geraint Evans gave a master-class and young composers were commissioned. There were also exhibitions of the work of artists, including Ceri Richards. For the last of the Dynevor Festivals, Malcolm Williamson was commissioned to write an opera based on Strindberg’s dream play The Growing Castle, which has had many revivals since. Eventually the festivals ended because Arts Council funding was no longer available. Newton House and the rest of the estate have been run by the National Trust since 1990.

Lord Dynevor also published books under the imprint Black Raven Press — a raven is in the Dynevor coat of arms. The first off the press was a collection of poems by Peter Levi, Fresh Water, Sea Water. Later came The Taliesen Tradition by Emyr Humphreys and a play by James Hanley, The Inner Journey, once performed at the Lincoln Centre in New York. In 1985 a history of Wales, When Was Wales? by Gwyn Williams was published.

Dynevor’s marriage to Lucy Rothenstein was dissolved in 1978, and he is survived by three daughters and a son.

Lord Dynevor, patron of the arts, was born on June 19, 1935. He died of cancer on November 12, 2008, aged 73