The principal miners' trade union in Britain is the National Union of Mineworkers (NUM), which was established in 1944. It developed from the Mineworkers' (Miners' until 1932) Federation of Great Britain (MFGB), a loose grouping of local associations founded in 1889.
Although the Modern Records Centre holds some publications of the MFGB, and its constituent associations, and the NUM, 1888-1992, we have no membership records. The main series of national records is still held by the NUM at its headquarters in Barnsley. Researchers should contact the union directly to enquire about accessing their central archives.
National Union of Mineworkers
2 Huddersfield Road
Significant trade union archives relating to the collieries of South Wales are included in the South Wales Coalfield Collection at Swansea University. Other trade union branch and district records can be held by local authority record offices. The National Register of Archives (searchable through the National Archives catalogue) lists some of these.