After a primary school education in South Australia Hales worked in the outback in a number of occupations, and began to contribute stories of his experiences to provincial newspapers. For some years he was a reporter at Broken Hill. Many of his stories were published in the collection Wanderings of a Simple Child (1890). The success of this publication enabled him to travel to America and England.
Returning to Australia he began the newspaper Australian Standard, later going to the WA goldfields and starting the Coolgardie Mining Review. His plant was destroyed by fire and he moved to Boulder City where he and his brother started the Boulder Star. He stood (unsuccessfully) as a Labour candidate for the WA parliamentary seat of Coolgardie.
Hales was a war correspondent for the London Daily News at the time of the Boer War, during which he was taken prisoner, served as an officer in the Macedonian rebellion against the Turks in 1903, and was Special Correspondent for the Daily News during the Russo-Japanese War. He also served as a war correspondent in World War One. His first adventure novel, Driscoll, King of Scouts (1901) was a story of the Boer War.
After this he lived mainly in England, writing a large number of adventure novels based on people he knew and places he had visited. Many of these featured McGlusky, an Australian of Scots descent. They proved enormously popular and sales are believed to have reached approximately two million. Several of his adventure novels were written for boys. He published a volume of verse in the bush ballad style of the time, Poems and Ballads (1909) and biographical works My Life of Adventure (1918) and Broken Trails (1931). He also wrote plays but none were published.
