| Regimental number | 2438 |
| Place of birth | Karridale, Western Australia |
| Religion | Roman Catholic |
| Occupation | Fireman |
| Address | PO, Yarloop, Western Australia |
| Marital status | Single |
| Age at embarkation | 26 |
| Next of kin | Father, G Brennan, Hoffman Mill, Western Australia |
| Enlistment date | 12 May 1915 |
| Rank on enlistment | Private |
| Unit name | 16th Battalion, 7th Reinforcement |
| AWM Embarkation Roll number | 23/33/3 |
| Embarkation details | Unit embarked from Fremantle, Western Australia, on board HMAT A51 Chilka on 18 June 1915 |
| Rank from Nominal Roll | Private |
| Unit from Nominal Roll | 16th Battalion |
| Fate | Returned to Australia 9 February 1919 |
| Family/military connections | Brother: 2574 Lance Corporal James William BRENNAN, 51st Bn, returned to Australia, 1 May 1919. |