| Regimental number | 1380 |
| Place of birth | Galway, Ireland |
| Religion | Roman Catholic |
| Occupation | Labourer |
| Marital status | Single |
| Age at embarkation | 42 |
| Height | 5' 8" |
| Weight | 158 lbs |
| Next of kin | Brother, Michael Joseph Byrnes, Clifden, Galway, Ireland |
| Previous military service | Served for 10 years in the Dragoon Guards and Rennington Scouts. |
| Enlistment date | |
| Place of enlistment | Brisbane, Queensland |
| Rank on enlistment | Private |
| Unit name | 2nd Light Horse Regiment, 11th Reinforcement |
| AWM Embarkation Roll number | 10/7/3 |
| Embarkation details | Unit embarked from Sydney, New South Wales, on board HMAT A47 Mashobra on |
| Rank from Nominal Roll | Driver |
| Unit from Nominal Roll | 2nd Division Ammunition Column |
| Fate | Returned to Australia |
| Discharge date | |
| Other details |
War service: Egypt, Gallipoli, Western Front Embarked Sydney, 4 October 1915; taken on strength of 1st Light Horse Railroad Company, Heliopolis, Egypt, 1 March 1916; taken on strength of 2nd Divisional Ammunition Column, Zeitoun, 10 March 1916. Proceeded from Alexandria to join the British Expeditionary Force, 20 March 1916; disembarked Marseilles, France, 27 March 1916; mustered as Driver, 15 May 1916. Admitted to 2nd Auxiliary Hospital, Southall, England, while on leave, 19 January 1917; discharged from hospital and granted leave, 6 February 1917. Marched in to No 2 Command Depot, Weymouth, 16 February 1917. Commenced return to Australia on board HT 'Barambah', from Plymouth, 8 April 1917; disembarked Brisbane, 9 June 1917; discharged, 11 June 1917 (medically unfit: defective vision). Medals: 1914-15 Star, British War Medal, Victory Medal |
| Sources | NAA: B2455, BYRNES John James |