His father, Patrick Knight O'Hara, a primary school teacher in the education department, Victoria, also published two volumes of verse.
During a period of eight years, of 28 first-class honours gained by all the schools of Victoria in physics and chemistry, 14 were obtained by pupils from South Melbourne College.
O'Hara was an inspiring teacher, and many of his pupils have since held distinguished positions in the universities of Australia.
All these volumes were favourably received by the press, and in 1919 a critic in The Times Literary Supplement spoke of O'Hara as a "singer who takes his place in the company of representative English poets".
As a boy he met Marcus Clarke, and was friendly with William Gay, Brunton Stephens, John Farrell and other literary men of his period.