| Date of birth | |
| Place of birth | Mount Perry, Queensland |
| School | South Brisbane State School; Brisbane Grammar School, Queensland |
| Religion | Church of England |
| Occupation | Accountant |
| Address | Sorrento, Edmondstone Street, South Brisbane, Queensland |
| Marital status | Single |
| Age at embarkation | 30 |
| Next of kin | Father, Octavius Armstrong, 'Sorrento', Edmondstone Street, South Brisbane, Queensland |
| Enlistment date | |
| Rank on enlistment | Lieutenant |
| Unit name | 25th Battalion, 2nd Reinforcement |
| AWM Embarkation Roll number | 23/42/2 |
| Embarkation details | Unit embarked from Sydney, New South Wales, on board HMAT A9 Shropshire on |
| Rank from Nominal Roll | Major |
| Unit from Nominal Roll | 9th Battalion |
| Promotions |
Captain Unit: 9th Battalion Promotion date: |
| Other details from Roll of Honour Circular | Joined the Bank of New South Wales, Brisbane branch, 16 January 1904 (appointed ledger keeper, 1 January 1908); transferred to South Brisbane branch (as teller), September 1910; to Brisbane branch, January 1911; to Bowen branch, August 1913. |
| Fate | Effective abroad (still overseas) |
| Other details |
Served as Provisional 2nd Lieutenant, 2nd Infantry Bn, Thursday Island (garrison duty), from August 1914. Enlisted in the AIF, 18 June 1915. War service: Egypt, Western Front Medals: 1914-15 Star, British War Medal, Victory Medal |