Catherine Marshall was a vital figure in the women's suffrage movement in Britain before the First World War. Using her remarkable political skills on behalf of the major non-militant organization, the National Union of Women's Suffrage Societies, she built close connections with major suffragist politicians, leading some - in all three parties - to consider adopting a measure of women's enfranchisement as a party plank.

By 1913 Marshall was uniquely placed as a lobbyist, with inside information and sympathetic listeners in every party. Through her the dynamically reorganized NUWSS brought the women's suffrage issue to the fore of public awareness. It pushed the Labour Party to adopt a strong stand on women's suffrage and raised working-class consciousness, re-awakening a long-dormant demand for full adult enfranchisement. Had the general election due in 1915 taken place, NUWSS financial and organizational support for the Labour Party might well have been substantial enough to influence the final results.