Born in Ballarat, Victoria Horse trainer by Occupation, Thomas William Brain was 35 years and married when enlisted on the 20th of June 1916 in the 8th Battalion, 21st Reinforcement, Australian Imperial Force, with the rank of Private, Number 6471. His Unit embarked from Melbourne, Victoria, on board HMAT A71 'Nestor' on the 2nd of October 1916. On the 26rd of April 1917 admitted to 6th Australian Field Ambulance Gonorrhoea; on the 4th of May 1917 transferred to 51st General Hospital, Etaples; on the 19th of May 1917 admitted to 3rd London General Hospital – Haemorrhoida. On the 28th of August 1917 left England for return to Australia per 'Pakeha' and disembarked at Melbourne on the 10th of December 1917; discharged from the A.I.F. at Melbourne as Medically Unfit – disability – Haemorroida and Defective Vision. Tree No. 3444