Thomas Gatehouse was born in Geelong in August 1888. He enlisted for overseas service on 14 July, 1915, when he was 26 years and 11 months old. He was a single man and worked as a groom. He appears to have been without close family, giving as his next of kin his friend, Miss Minnie Costain. Tom Gatehouse lived at 167 Wellington Street, Jolimont, a boarding house owned and run by Minnie Costain. Minnie Cosain was before the court in 1912, accused of owning and running 'a disorderly house', that is, a brothel, a charge subsequently dismissed. In 1917, she was again before the court for selling sly grog, but again, this was dismissed, the police involved having gone to her boarding house in disguise to entrap her. Interestingly, she also owned a garage and car in 1917.

Tom Gatehouse would have trained at Albert Park and been chosen for the 3rd Reinforcements of the 4th Field Artillery Brigade because of his knowlege of horses, which were used to move the guns into place on the battlefield. The 3rd Reinforcements left Melbourne on 28 January, 1916, on board HMAT Themistocles A32 and were taken on strength at Zeitoun, Egypt, a large army camp for the ANZAC troops outside Cairo, but with easy access if needed to defend of the Suez Canal. Here the reinforcements joined the 4th Field Artillery Brigade.The 4th FAB now joined the 2nd Division and the older AIF units following their withdrawal from Gallipoli in December, 1915. In March 1916, they embarked at Alexandria for France, disembarking at Marseilles, then taking an 800 kilometre train hourney to Le Havre, where they collected their eighteen-pounder guns, four to a brigade. From here, they travelled on to the French-Belgium border and settled in to the 'nursery sector' at Armentieres on 8 April. On 2 May, Tom Gatehouse was ill and admitted to the 5th Ambulance Station, before being discharged to duty on 9 May. He was then transferred to the 2nd Division Amunition Column to fight in the Somme offensive. In late July, he would have been at Pozieres and in constant action against the Germans. 

Tom Gatehouse was returned to the 4th FAB  on 8 November, 1916, when both sides endured the bitter winter of 1916-17. In March, 1917, they were at Bullecourt and in May, Tom Gatehouse was charged with being AWL, from 19-20 June. He was given 14 days Field Punishment. On 19 July, he was transferred from the 11 Battery to the 1oth. By now a gunner of some experience, this would not have been unusual. In August, he was admitted to  the 18th General Hospital at Camiere with a discharge from his ear and remained there until 24 September, when he was transferred to the 2nd District Artillery Column, before moving back to the 11 Battery, 4 FAB, on 30 September. Given leave in England in October, he returned to battle until November, when he was again ill, with a middle ear infection and was transferred first to the 5th Field Ambulance Station, then to hospital at Wimereux. On 4 November, he was at a convalescent camp, then on 11 November was sent to the 3rd Rest Camp at Boulogne. His condition must have recurred, because on 17 November, he was back in hospital at at Boulogne, then sent on to the 4th Convalescent Depot at Havre.

He was finally discharged to Base Depot, where he misbehaved again and was charged with 'irregular conduct in a Mess Hut' and given 10 days Field Punishment, before returning to the 2nd DAC. his health was by now deteriorating: he had balanitis, a venerial disease, and was in hospital for 55 days at Havre, before being discharged on 5 February, 1918. He was returned to England where he worked at the Australian Employment Company at District Head Quarters, presumably in London. Given leave on 20 October, he was admitted to hospital with aneamia on 23 October, then sent on to convalescence at the No.2 Command Depot at Weymouth.

He left England for return to Australia on 20 November, 1918, on HS Suevic, disembarking at Mlebourne on 5 January, 1919. He was discharged from the army on 19 April, described as being unfit as a result of disability, debility and post-influenza.

From here, it is impossible to trace him, both because he has no second name to distinguish him from other Thomas Gatehouses and becaause he never named his parents on any army form. Nor did he return to Minnie Costain's Boarding House. A Thomas Gatehouse died in 1962 in Heidelberg, presumably the Reptriation Hospital, but it is uncertain whether this was him.