With 500,000 members, the National Union of Mineworkers, formed after the second world war, was a force to be reckoned with. In its early years, disputes were settled without resorting to industrial action. But in the 1970s, it became more militant. Strikes led to the ‘three-day week’, when electricity had to be rationed, and caused the downfall of the Conservative government of Edward Heath in 1974.
But in 1984, the union met its nemesis. Margaret Thatcher had been prime minister for five years by then, and had recently dealt with the steelworkers. Britain’s mines were uneconomic; she wanted to close the unprofitable ones and sell off the rest.
There was a skirmish in 1981, when the government planned to close 23 pits, but the threat of a strike was enough to make them back down. But by 1984, Thatcher was ready for a fight.
To avoid a repetition of the disastrous three-day week, she had coal stockpiled at power stations. Then she made her move. 20 pits were to close, and 20,000 jobs would be lost.
And so, on 5 March 1984, miners at Cortonwood Colliery in South Yorkshire walked out. It was the start of what would turn out to be one of Britain’s most acrimonious industrial disputes.
Within six days, miners from Scotland to Kent had come out on strike. ‘Flying pickets’ travelled the country to protest – sometimes violently – and prevent mines from being worked and coal from being moved. Police were mobilised on a military scale to combat them. Pitched battles were fought.
The strikers’ solidarity was severely dented when Nottinghamshire miners voted to form a breakaway union and return to work, causing bitter resentment – which is still felt in some parts of the country.
Eventually, however, the miners were beaten. On 3 March 1985 they returned to work. The once-powerful NUM was reduced to irrelevance. By 2013, it had fewer than 1,300 members.