| Regimental number | 10150 |
| Place of birth | Lewisham New South Wales |
| Religion | Roman Catholic |
| Occupation | Clerk |
| Address | 'Locksley', The Avenue, Petersham, New South Wales |
| Marital status | Single |
| Age at embarkation | 23 |
| Next of kin | Father, William Richard Darby, 'Locksley', The Avenue, Petersham, New South Wales |
| Enlistment date | |
| Rank on enlistment | Gunner |
| Unit name | Reinforcement 2 |
| AWM Embarkation Roll number | 13/33/2 |
| Embarkation details | Unit embarked from Sydney, New South Wales, on board HMAT A35 Berrima on |
| Rank from Nominal Roll | Private |
| Unit from Nominal Roll | 4th Field Artillery Brigade |
| Fate | Died of wounds |
| Miscellaneous details (Nominal Roll) | *Spelt James Butler Darby on NR |
| Age at death from cemetery records | 26 |
| Panel number, Roll of Honour, Australian War Memorial | 13 |
| Miscellaneous information from cemetery records | Parents: William Richard and Mary DARBY |
| Family/military connections | Brother: 10149 Pte William Stanislaus DARBY, Australian General Base Depot, returned to Australia, 11 May 1919. |
| Other details |
War service: Western Front Medals: British War Medal, Victory Medal |