Born in Darlinghurst, Sydney, he left home at 15 and for five years lived the life of an adventurer, claiming to have had twenty-five different jobs by the age of 17, and enlisting with the US Army in Kansas 26 October 1911, deserting and going to sea. He joined the AIF in 1915 and was soon with the 16th Battalion at Gallipoli and repatriated a year later, wounded in both legs.

He married in 1916 and divorced in 1920, remarried in 1923, established himself as a tax consultant and by 1930 had settled in Vaucluse and in 1933 published Try Anything Once, an account of his adventures. Many of his subsequent books were in collaboration with P R 'Inky' Stephensen, notably The Viking of Van Diemen's Land and The Pirates of the Brig 'Cyprus'.

He was clearly fascinated by the 'outsiders' of Australian history such as Captain Melville, Captain Starlight, Martin Cash, Edward Hargraves, Bully Hayes, Jorgen Jorgenson, Chinese Morrison, Ben Hall, Ned Kelly, Frederick Bailey Deeming and Louis de Rougemont

Clune also wrote for magazines such as Smith's Weekly and A. B. C. Weekly. He broadcast "Roaming Round Australia" regularly on The ABC from 1945 — 1957.

Clune was an effective promoter of Albert Namatjira and Australian aborigines generally.

Clune had his detractors. He was criticised for embroidering the facts in the interests of the narrative, and was met with hostility by General Sir Thomas Blamey for his "irregular methods and indiscreet utterances" during WWII.

The tax accounting business he founded with his son continues to this day.

Clune's portrait was painted by Sir William Dargie and Sir William Dobell.

He was awarded the OBE in 1967.

Clune's 1959 book Jimmy Governor was the inspiration for Thomas Keneally's 1972 novel The Chant of Jimmie Blacksmith.His published books include: