| Regimental number | 1609 |
| Place of birth | Palmer, South Australia |
| Religion | Church of England |
| Occupation | Store keeper |
| Marital status | Single |
| Age at embarkation | 31 |
| Height | 5' 10" |
| Weight | 168 lbs |
| Next of kin | Father, Henry Conrad Mengersen |
| Previous military service | Nil |
| Enlistment date | |
| Date of enlistment from Nominal Roll | |
| Place of enlistment | Cairns, Queensland |
| Rank on enlistment | Private |
| Unit name | 25th Battalion, 1st Reinforcement |
| AWM Embarkation Roll number | 23/42/2 |
| Embarkation details | Unit embarked from Brisbane, Queensland, on board HMAT A60 Aeneas on |
| Rank from Nominal Roll | Lieutenant |
| Unit from Nominal Roll | 25th Battalion |
| Promotions |
Lieutenant Unit: 25th Battalion Promotion date: 2nd Lieutenant Unit: 25th Battalion Promotion date: |
| Fate | Died of wounds |
| Age at death from cemetery records | 24 |
| Place of burial | Menin Road South Military Cemetery (Plot I, Row T, Grave No 34), Ypres, Belgium |
| Panel number, Roll of Honour, Australian War Memorial | 105 |
| Miscellaneous information from cemetery records | Parents: Parents: Henry and Emily MENGERSEN, Palmer, South Australia |
| Family/military connections | Brothers: 554 Pte Charles Herman MENGERSEN MM, Australian Motor Transport Section, returned to Australia, 23 December 1919; 4560 Sergeant Irwin Oscar MENGERSEN DCM, 50th Bn, returned to Australia, 4 July 1919; 4163 Pte Norman Victor MENGERSEN, 25th Bn, returned to Australia, 25 August 1917. |
| Other details |
War service: Egypt, Gallipoli, Western Front Medals: 1914-15 Star, British War Medal, Victory Medal |
| Miscellaneous details | Name does not appear on Embarkation Roll. |
| Sources | NAA: B2455, MENGERSEN Herman Edgar |