[3][4] Watters was aware of the dispute leading to the Asturian miners strike where workers were attacked by the Spanish Foreign Legion and Moroccan Regulares, as the right-wing government sought to crush the uprising.
He served in the International Brigade during the Spanish Civil War, departing for Spain in November 1936,[5] with his wife Ellen's support, although leaving her and three children.
In comparison, percentage-wise, the British army lost 12.5 per cent of their men during the six years of the Second World War[1]Captured, Watters was sentenced to indefinite solitary confinement.
[7][1] The parade of International Brigades leaving Barcelona was supported by a large crowd, and shouts of 'No Pasaran' and singer Dolores Ibárruri, known as La Pasionaria, said to the volunteers “We shall not forget you; and, when the olive tree of peace is in flower, entwined with the victory laurels of the Republic of Spain – return!
"Return to our side for here you will find a homeland – those who have no country or friends, who must live deprived of friendship – all, all will have the affection and gratitude of the Spanish people who today and tomorrow will shout with enthusiasm – Long live the heroes of the International Brigades!”[1]Back home, Watters had difficulty finding employment, even in the mines, as did some others who had been communists.
Later he was elected chairman of the National Union of Mineworkers for twenty years at Prestonlinks Colliery, then when it closed moved to Monktonhall pit.