Walter Henri de Morton was over age when he enlisted on 11 December, 1916. He gave his age as 39, but was already 47. He was a widower and gave as his next of kin his son, Edward David De Morton. They both lived at 138 Lake St., Perth. Walter was a railway employee and gave his. Employment as 'checker'. The eagerness for more recruits may have assisted him: the Hughes Labor Government's first Conscription Plebiscite had failed, while casualties at the Western Front were horrific. At training at Black Boy Camp, he was placed with the 28th Battalion had been raised in Western Australia in June 1915. After two months' training in Egypt, they had landed at Gallipoli on 10 September and were evacuated in December 1915 and sent to France. They had been in combat at Pozieres in July-August 1916, then moved to Flnders, returning to France in October to fight at Flers in the battle of the Somme. Walter de Morton embarked on 29 January, 1917, from Fremantle on HMAT Militiades A28, disembarking at Devonport, UK, on 27 March. He marched in to the 7th Training Battalion at Rolleston the next day. By the next month, he was ill and sent to Fargo Hospital, where he was diagnosed with Pyrotis, then Pyrexia. He was there a month, from 15 April to 10 May, 1917, then spent another two weeks in England, before joining his battalion in France. On 5 October, he was finally taken on strength , but by the 31 October, he was back in hospital. He returned to England from the 2nd ADB, coming out from Havre and in to Weymouth. He was sent to the No.2 Convalescent Depot at Sutton Veny. On 1 January, 1918, he boarded the Balmoral Castle and was discharged from further service on 9 April. There are two medical reports in Walter De Morton's record: 'Was in France 3 months ( 1 month hospital) prior to which was in hospital in England with myalgia. Suffered from bronchitis for years.' The other report, co-signed by Majors P.M. O'Meara and S.C. Moore read ' husky voice, poor physique, older than his years. Heart enlarged. Sounds lack tone. Lung emphysema and chronic bronchitis.' A further report stated ' over age 48 years. looks older. chr. bronchitis. Chest emphysematic. Condition not aggravated by service.'

Walter de Morton returned to Perth and rejoined the WAG Railways. He died in June, 1925, with a notice from his family and his union (the WAAS of Railway Employees) appearing in the West Australian of 19 June 1925.