[2] Dunn had a varied career as a journalist across various newspapers and magazines in Scotland, England and South Africa until his death in 1919, "Moving between the metropolis and the provinces so as to belong almost equally to both.

Dunn remained in this role "in its prime" under editor William Ernest Henley until 1893 when he resigned to join the staff of The Pall Mall Gazette.

[1] From 1897 to 1905, Dunn was editor of the London newspaper The Morning Post, a conservative London-based daily whose editorship "was marked by such an advance in the political weight of that paper.

Dunn was President during "a rather stormy period" of the Institute but "by his urbanity and good humour, weathered a difficult situation, to the complete satisfaction of every one who had to work with him.

[1] As a journalist and editor, Dunn was in regular correspondence, and worked closely with, various writers during his career in London from the late 1880s to the early 1900s, a time when literary writings frequently featured in periodicals and there was much crossover between the worlds of literature and journalism.

[18][19] In 1895 and shortly after becoming editor of Black & White, Dunn sought out writings from American journalist and novelist Harold Frederic.