| Rank | Lieutenant |
|---|---|
| Unit | 2nd Australian Machine Gun Battalion |
| Conflict/Operation | First World War, 1914-1918 |
| Enlistment Date | 1915-01-20 |
| Fate | Discharged |
| Fate Date | 28 December 1919 |
First World War Nominal Roll Michael Joseph O'Brien
| Rank | Lieutenant |
|---|---|
| Unit | 2nd Australian Machine Gun Battalion |
| Conflict/Operation | First World War, 1914-1918 |
| Enlistment Date | 1915-01-20 |
| Fate | Discharged |
| Fate Date | 28 December 1919 |
