Colin Horne was the son of a commercial traveller in groceries, distinguishing himself at an early age in both his studies and in sport and winning a scholarship to Melbourne University at the age of sixteen. As this was not sufficient to live on, he taught at his old school and later attended the university on a teaching scholarship, gaining an MA from Melbourne University. Winning a scholarship to Oxford, he went on to gain an MLitt. He taught at Queen's University, Belfast and the University of Leicester before returning to Australia to take up the Jury Chair of English Language and Literature at the University of Adelaide in 1958. He retired in 1977.
Horne was active in his support of the arts, being, among other things, an inaugural committee member of the Adelaide Writers' Week and its chairman from 1969-1974. He also held positions on the International Association of Professors of English (1965-1983) and the Australian and Pacific Society for 18th Century Studies. He was a strong supporter of the State Library, being a member of the Friends for 41 years and their president for twelve years. In 1979 he was appointed a Member of the Order of Australia for services to education and literature.
Horne published a number of books on English literature, including Swift on his Age (1953), Four Hundred Years of Shakespeare 1564-1964 (1964) and the Pelican Guide to Australian Literature, vol. 4, 1957-1991.