In 1984, the National Coal Board (the UK Government department which controlled coal mining in that country) announced that an agreement reached after the 1974 miners' strike had become obsolete, and that they intended to close 20 pits (coal mines). 20,000 jobs would be lost, and many communities in the North of England and in Wales would lose their primary source of employment.
Sensitive to the impact of the proposed closures in their own areas, miners in various coal fields began strike action (industrial inaction). In the Yorkshire coal field strike action began on 5 March, following a local ballot, and on the next day pickets from the Yorkshire area appeared at pits in the Nottinghamshire coal field (one of those least threatened by pit closures). On 12 March, 1984 Arthur Scargill, President of the National Union of Mineworkers (NUM) declared that the strikes in the various coal fields were to be a national strike and called for strike action from NUM members in all coal fields.
Crucially, although there was widespread support for the strike amongst mine workers, Scargill did not call a ballot for national strike action. This mistake (or deliberate omission) allowed the Conservative government under Margaret Thatcher to bring the full weight of the law down on the striking miners and the union. The NUM's funds were seized on October 24, 1984 by order of the High Court. Miners were denied state benefits and their wages, and the police were mobilised to deal with picket lines on the grounds that they represented illegal public disturbances. The miners also split in various groups, such as that from Nottinghamshire, which formed the Union of Democratic Mineworkers (UDM).
A widely reported clash during the Miners' Strike took place at Orgreave near Rotherham on 18 June 1984. This confrontation between striking miners and police, dubbed by some as the Battle of Orgreave, was the subject of a TV re-enactment in 2001, conceived and organized by artist Jeremy Deller and recorded by Mike Figgis for the TV Channel 4.
The strike ended on March 3, 1985, nearly a year after it had begun, when the NUM conceded defeat.
Dame Stella Rimmington (MI5 Director General, 1992–1996) published an autobiography in 2001 in which she revealed MI5 'counter-subversion' exercises against the NUM and the striking miners, which included the tapping of union leaders' phones.