Tom Brennan was the son of John and Mary Brennan (nee Byrne) of Kilkenny, Ireland. Together with his brother Joseph, he migrated to Australia in the years prior to World War I. At the time he enlisted for military service in December 1914, he was living in Brisbane and was employed as a clerk.
During World War I, Brennan served as a stretcher bearer with the Australian Light Horse Brigade Field Ambulance, initially at Gallipoli, then in Egypt and Palestine. In August 1916, he was mentioned in despatches for his actions at Romini, and he was subsequently awarded the Military Medal for gallantry at Bir-Al-Abd (he refers to both Romini and Bir-Al-Abd in his Kia-Ora Coo-ee article 'Field Ambulances'). However, by war's end Brennan developed a severe psychiatric illness, and during 1919 he spent several months in English military hospitals, before being returned to Australia as a convalescent. He died of ‘exhaustion’ at Brisbane General Hospital in September 1920.
During World War I, as 'Brentomnan', Brennan's poetry and articles featured prominently in the Kia-Ora Coo-ee, and he was perhaps one of the magazine's more talented contributors. A number of his poems also appeared in the Cacolet, the magazine of the Australian Army Camel Field Ambulance, which he briefly edited.
Brennan was revealed as the author 'Brentomnan' (an anagram of 'Tom Brennan') in a November 1915 World's News item which included his poem 'Our Nameless Dead'. It is notable that Brennan's earliest known poem, 'The Men of the West', which was published in the Brisbane Worker in October 1911, also appeared under his writing name 'Brentomnan'.
Brennan's brother Joseph served as a private with the 9th Battalion AIF. He enlisted at about the same time as Thomas, and both left Brisbane together on HMAT Seang Choon on 13 February, 1915, bound for Egypt. Joseph was wounded at Gallipoli and died in hospital at Alexandria soon afterwards. Anthony, another brother, served with the Royal Irish Rifles during World War I. Post war, Anthony wrote an account of his wartime experiences, which is now held at the Imperial War Museum in London.
