Stanley was the eldest child of Augustus and Jane Hartmann. His birth was registered at Inverell in 1892. After twice being rejected for service, he enlisted at Liverpool NSW in February 1915 when he was twenty three years old.
Stanley joined the 2nd Battalion, 10th Reinforcement and sailed from Australia for Egypt on HMAT A69 Warilda in October 1915. After a few weeks he was transferred to the 54th Battalion and sent to France in June 1916. Just twenty days later Stanley was Killed in Action and buried at Croix-du-Bac British Cemetery, Steenwerck, France. His medals were sent to his family at Moruya NSW.