[2] Following the declaration of war on 4 August 1914 and the suspension of Suffragette Militancy,[19] Capper joined the Volunteer Aid Detachment.

[2] In 1908 Capper wrote to the Manchester Guardian to counter the objection to women's enfranchisement on the grounds that they would not be subject to conscription into the armed forces.

[21] In October 1912, Capper's play The Betrothal of Number 13 was produced at the Royal Court Theatre "of working class life, written with a certain amount of sympathetic insight and character" it concerned the stigma imposed by imprisonment, even on the innocent.

In 1963 she wrote of her friend Mary Gawthorpe 's father and "what it meant to be born into a North Country working class family (in) the eighteen-eighties....doomed by the caste system of (the) day to be a leather worker in an age when a stiff fight had to be made against competition from America."

In Capper's 1963 review of Gawthorpe's book Up Hill to Holloway, Capper described how, in 1904, Gawthorpe was called to make her first speech entitled The Children under Socialism "concerning the propriety of providing suitable food and clothing for poor children of the unemployed and needy during the winter" It was a time of economic depression and, "from the Labour point of view, the aftermath of the South African War."

By February a total of 323,414 dinners had been provided...Strictest economy was necessary, and lentils, at about one halfpenny a meal, appear to have been the basic diet.