Catherine Hay Thomson was educated in Melbourne and matriculated from Melbourne University (before female students were accepted). 'She was principal of Queen's College, Ballarat for some time and in 1881 opened a boarding and day school for girls in Spring Street, Melbourne. Later she began writing investigative articles, being referred to in the Bulletin in 1886 as "the female 'Vagabond' of Melbourne".'
In 1899, Thomson and Evelyn Gough became joint proprietors of the Sun: An Australian Journal for the Home and Society. Thomson later became a literary agent.
Clarke, Patricia. Pen Portraits: Women Writers and Journalists in Nineteenth Century Australia. Sydney: Allen & Unwin, 1988: 181.