It initially prioritised calling for waste ground to be sold cheaply to miners so they could set up their own works, and for workers to be represented on the local Board of Guardians.
A strike in 1871 at Parkend Colliery was successful in raising wages and led to the appointment of a checkweighman.
[1] In 1877, the general secretary, Timothy Mountjoy, was discharged, and the union became moribund until 1882, when it was reconstituted.
[1] Henry Rowlinson served as agent and secretary of the union from the 1880s until 1917, when his support for World War I became unpopular.
He was replaced by Jack Williams, soon to become a sympathiser of the Communist Party of Great Britain and prominent figure in the National Minority Movement, and the union began working frequently with the South Wales Miners Federation in supporting left-wing motions.