| Regimental number | 6463 |
| Place of birth | Ascot Vale, Victoria |
| School | Maylands State School, Western Australia |
| Religion | Church of England |
| Occupation | Optician |
| Address | 20 Seventh Avenue, Maylands, Western Australia |
| Marital status | Single |
| Age at embarkation | 21.2 |
| Height | 5' 4.25" |
| Weight | 128 lbs |
| Next of kin | Father, W A Cadwallader, 20 Seventh Avenue, Maylands, Western Australia |
| Previous military service | Served in the 88th Infantry, Citizen Military Forces; still serving at time of AIF enlistment. |
| Enlistment date | |
| Date of enlistment from Nominal Roll | |
| Place of enlistment | Perth, Western Australia |
| Rank on enlistment | Private |
| Unit name | 11th Battalion, 21st Reinforcement |
| AWM Embarkation Roll number | 23/28/4 |
| Embarkation details | Unit embarked from Fremantle, Western Australia, on board HMAT A23 Suffolk on |
| Rank from Nominal Roll | Lance Corporal |
| Unit from Nominal Roll | 11th Battalion |
| Fate | Killed in Action |
| Place of death or wounding | Meteren, France |
| Age at death | 23 |
| Age at death from cemetery records | 23 |
| Place of burial | Meteren Military Cemetery (Plot I, Row A, Grave 42), France |
| Panel number, Roll of Honour, Australian War Memorial | 61 |
| Miscellaneous information from cemetery records | Parents: William Augustus and Elizabeth CADWALLADER |
| Other details |
War service: Western Front Medals: British War Medal, Victory Medal |
| Sources | NAA: B2455, CADWALLADER Oliver Harry |