Wiradjuri man Private Gilbert Williams was born in Gonelie, New South Wales, in 1892. As a widower, he worked as a bushman to support his only child, Allan. He chose to enlist in 1917 at a time when recruitment numbers were difficult to sustain. Although there were restrictions against Aboriginal men enlisting, Gilbert signed up at Broken Hill on 3 April 1917, stating that he was a natural-born subject.
With his experience with horses and the bush Gilbert was allotted to the 3rd Light Horse Regiment, which had been raised in South Australia. In 1915 the regiment served on Gallipoli in a defensive infantry role, having left their horses in Egypt. Returning to Egypt after the Gallipoli campaign it joined forces defending the Suez Canal. Throughout the next three years, the regiment fought as part of the 1st Brigade in battles at Romani, Magdhaba and Gaza, pushing back enemy positions and occupying the west bank of the Jordan River.
However, Gilbert was not to join his regiment overseas. Two months into his training he required medical attention and was hospitalised for several months on Torrens Island. Shortly after his release from hospital, despite having committed to serving until a year after the war's end, Gilbert was discharged from the service. His discharge papers declared that he was “medically unfit for further service”. Further investigation into Gilbert’s service records show that the medical officer declared him to be an Aboriginal with a “deficient physique”.
It is unknown what became of Gilbert after he was discharged.