Rt. Hon. David Rhys Grenfell was born in 1881 at Penrheol, Gorseinon. He was the son of a coal-miner and he himself went to work underground aged 12 in 1893. He continued to work in the mine for 23 years. During that time he also studied and eventually qualified as a Colliery Manager. In 1905 he married Beatrice Morgan and they had a daughter, Eileen in 1907. In1916 he became a Miners' Agent. He became prominent in the local labour movement and in 1920 was adopted as prospective Labour candidate for Gower. He first won the seat in 1922, holding it until 1959.
David Rhys Grenfell took a great interest in the concerns of the miner and had a significant part inthe negotiations which led to the Coal and Cattle Agreement of 1935. He sat on the Miners' Welfare Scholarship Committee 1930-1935 and was a member of the Royal Commission on Safety in Mines 1935-1938. In 1940 he was chosen by WinstonChurchill to be the Secretary for Mines, a position he held for two years. He later became Chairman of the Welsh Parliamentary Party. He was often known as `Dai'. He died in 1968.