| Rank | Major |
|---|---|
| Unit | 6th Australian Light Horse Regiment |
| Conflict/Operation | First World War, 1914-1918 |
| Enlistment Date | 1914-10-09 |
| Fate | Returned to Australia |
| Fate Date | 03 August 1918 |
First World War Nominal Roll Harold Ormond O'Brien
| Rank | Major |
|---|---|
| Unit | 6th Australian Light Horse Regiment |
| Conflict/Operation | First World War, 1914-1918 |
| Enlistment Date | 1914-10-09 |
| Fate | Returned to Australia |
| Fate Date | 03 August 1918 |
