He was born at Fforest-fach, Swansea, probably in 1884 (although some sources give the year of his birth as 1885), the son of William Mainwaring and his wife. Both his parents were natives of Swansea. He was educated at St Peter's National School, Cocket. He began work as a coalminer at the Cambrian Colliery, Clydach Vale at the age of thirteen in 1897, and served as secretary to the SWMF Minority Group, 1909-13. From his early years, he developed a deep interest in educational and industrial issues. He played a prominent part in the 1910 miners' strike and was considered as, first and foremost, a mineworkers' leader. He also spent two years at the Central Labour College in London. He was subsequently secretary to the Unofficial Reform Committee and was joint author (with Noah Ablett) of The Miners' Next Step (1912), a highly publicised syndicalist manifesto suggesting how ownership and control of the coal pits should change. He applied to be general secretary of the MFGB, and thus became involved in the closest ballot in the history of the south Wales coalfield. When Frank Hodges left the position of general secretary to the MFGB, Mainwaring and A. J. Cook engaged in a great tussle to secure the south Wales nomination for the vacant position. When the votes were counted, it was found that Cook had gained the nomination by just over 500 votes - 50,123 votes for Cook and 49,617 votes for Mainwaring. He was appointed secretary of the International Mineworkers' Federation, but he never took up the position. He was a conscientious objector during World War I. After the war he returned to the Central Labour College where he lectured in economics and served as vice-principal, 1919-24. He succeeded A. J. Cook as the miners' agent for the Rhondda no. 1 district of the SWMF, the largest district in the whole of the south Wales coalfield, serving from 1924 until 1934.
Mainwaring was elected as the Labour MP for the Rhondda East division in a by-election in 1933 following the death of the sitting Labour MP, Colonel D. Watts-Morgan. But his election to parliament was by no means a foregone conclusion. He was opposed by Arthur Horner as a Communist candidate, and a Liberal also stood. Mainwaring's majority over Horner was just 2,899 votes, while the Liberal came in third. The constituency was a stronghold of Communism, and in each subsequent parliamentary election Mainwaring faced a Communist opponent. He twice defeated the redoubtable Harry Pollitt, although his majority in 1945 was no more than 972 votes. Strangely, in the general election of February 1950, when Pollitt stood again (for the last time) the margin between them was a massive 22,182 votes. He was opposed by Annie Powell as the Communist aspirant there in 1955. Mainwaring continued to represent Rhondda East until he resolved to retire from parliament in 1959. He often spoke in the House of Commons with passion and fire on behalf of his fellow miners. Mainwaring was notably well travelled. He served as a member of the Royal Commission on Rhodesia and Nyasaland in 1938. In 1943 he was selected by the Inter-Parliamentary Union to tour the East African territories, and he also spent four months in the USA undertaking an economic investigation. He toured Asia in 1956. A small group of his papers is in the custody of the National Library of Wales. A native Welsh speaker, he lived at 11 Aubrey Road, Penygraig in the Rhondda valley and also owned a home at 18 Harbord Road, Oxford. He married in 1914 Jesse, the daughter of Thomas Hazell of Oxford. They had one daughter. His wife had predeceased him. He died on 18 May 1971 aged 87. After a private cremation at Oxford his ashes were interred at Glyntaff Crematorium.
Published date: 2008-09-17
Article Copyright: http://rightsstatements.org/page/InC/1.0/
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