| Regimental number | 2221 |
| Place of birth | Sydney New South Wales |
| Religion | Roman Catholic |
| Occupation | Labourer |
| Address | Lismore PO, Lismore, New South Wales |
| Marital status | Single |
| Age at embarkation | 36 |
| Next of kin | Father, Frederick Charles O'Brien, Molesworth Street, Lismore, New South Wales |
| Enlistment date | 9 September 1915 |
| Rank on enlistment | Private |
| Unit name | 5th Light Horse Regiment, 15th Reinforcement |
| AWM Embarkation Roll number | 10/10/4 |
| Embarkation details | Unit embarked from Sydney, New South Wales, on board HMAT A67 Orsova on 11 March 1916 |
| Rank from Nominal Roll | Private |
| Unit from Nominal Roll | 2nd Light Horse Regiment |
| Fate | Returned to Australia 17 July 1919 |
