Little is known of Cumine's life prior to 1914. Australian War Memorial records indicate that he volunteered for military service in August 1914, and that at the time he was living in Hobart. His occupation is stated as 'university student'. During World War I, Cumine served at Gallipoli as a sapper in the 2nd Field Company Engineers, and later in France in the 13th Field Company Engineers. At war's end he had attained the rank of sergeant. He returned to Australia in December 1918.
By the early 1920s Cumine was living in Sydney, where he gravitated within bohemian circles and became friendly with Dulcie Deamer, Christopher Brennan, artist George Finey, and others. Throughout the 1920s and 1930s he lived a meagre existence, supporting himself through his writing and by working at odd jobs. During this period he also became involved in radical left wing politics, and wrote a string of anti-war poems, which were published in Smith's Weekly, Truth, the Labor Daily and in the Australian Railway Union magazine Railroad. During the early stages of World War II, Cumine's radicalism attracted the interest of the authorities, and at one point his library was temporarily confiscated by police and his mail was intercepted.
Notoriously eccentric, Cumine was plagued by alcoholism and mood swings. He also suffered from a painful and debilitating arm injury, which later required amputation. In 1947 he admitted himself to Callan Park Hospital. He died at the Bare Island home for war veterans at La Perouse, in Sydney in 1953.
