| Regimental number | 1666 |
| Religion | Roman Catholic |
| Occupation | Constable |
| Address | People's Palace, Pitt Street, Sydney, New South Wales |
| Marital status | Single |
| Age at embarkation | 40 |
| Next of kin | Brother, Timothy O'Brien, Bellucolhue, Limerick, Ireland |
| Enlistment date | 27 September 1915 |
| Rank on enlistment | TPR |
| Unit name | Australian Remount Unit 2, Squadron 6 |
| AWM Embarkation Roll number | 28/3/2 |
| Embarkation details | Unit embarked from Sydney, New South Wales, on board HMAT A67 Orsova on 10 November 1915 |
| Rank from Nominal Roll | Trooper |
| Unit from Nominal Roll | 7th Mobile Veterinary Section |
| Fate | Returned to Australia 1 January 1919 |