In January 1891 a revolutionary struggle broke out between the ‘Constitutionalists’ or ‘Congressists’ (the revolutionaries, who were in fact the supporters of the Parliament) and the ‘Balmaceditas’ (the loyalists, named for President Manuel Balmaceda, who favoured a strong executive). The principal Congressist combatants were naval units, but on the presidential side the railway network was widely used in the movements of troops on land. On 15 February, locomotives sent to break through Congressist lines were used by presidential troops to concentrate at Huara, where Colonel Robles was victorious.
In the struggle for the northern ports, the Congressists used an armed locomotive and an armoured train with two machine guns. It carried out reconnaissance missions leading up to the battle of Pozo Almonte on 7 March, then took part in the battle itself, which saw the rout of the Presidential troops under Colonel Robles and the death of the latter. The civil war ended on 28 August 1891 with the victory of the insurgents.
It should be noted that an armoured wagon for the transport of explosives is currently kept at Copiapó Museum in Atacama Province, but there is no indication that this wagon was involved in the civil war.