The daughter of Daniel and Rosetta (née Kelly) John, Cecilia John came to Melbourne during her early teens to study music and singing. To pay for her training she established a poultry farm at Deepdene. By 1911 John was a successful teacher of singing and voice production as well as a poultry expert. She also joined the Collins Street Independent Church, distributed anti-conscription literature for the Australian Freedom League and supported Vida Goldstein in her campaign for election to Federal parliament in 1913.

A member of the Women's Political Association she wrote for the Woman Voter and with Goldstein established the Women's Peace Army and became its financial secretary. At anti-conscription meetings she sang 'I Didn't Raise My Son to Be a Soldier' until banned by the government under the War Precautions Act of 1915. She also formed the Children's Peace Army and the People's Conservatorium. Along with Ina Higgins, John ran a women's co-operative farm, the Women's Rural Industries Co. Ltd, at Mordialloc, providing employment to women in financial need.

Following World War I John attended the Women's International Peace Conference at Zurich with Goldstein. She also worked for the International Red Cross in Geneva and the Save-the-Children Fund in London where she became involved with the Dalcroze Eurhythmic system of dancing. In 1932 John became principal of the London School of Dalcroze Eurhythmics, a position she held until her death on 28 May 1955.

Sources used to compile this entry: Bomford, Janette M., That dangerous and persuasive woman : Vida Goldstein, Melbourne University Press, Carlton, Vic., 1993, 264 pp; Caine, Barbara (ed.), Australian Feminism: A Companion, Oxford University Press, Melbourne, 1998, 607 pp; Gowland, Patricia, 'John, Cecilia Annie (1877 - 1955)', in Australian Dictionary of Biography Online, Australian National University, 2006, http://www.adb.online.anu.edu.au/biogs/A090484b.htm; Sparrow, Jeff and Sparrow, Jill, Radical Melbourne : a secret history, the vulgar press, Carlton North, Vic., 2001, 223 pp.