According to the US 1910 census, William emigrated to Chicago in 1906, and was followed by Jessie in 1907. William worked as an electrician, and in 1910 was living at 1116 North Central Ave, Chicago with his wife Jessie, and daughters Jessie (born 1908) and Dorothy (born 1910). Sometime after the birth of his son Norman in 1912, the family moved to Fort William, Ontario, Canada, and William took up a job as a policeman with the Canadian Pacific Railroad.
On May 31, 1915, William joined up with the Canadian Over-Seas Expeditionary Force. On his attestation papers, he is described as 5’8” of fair complexion with blue eyes and brown hair. Jessie had already returned home to Birmingham, taking the children with her.
Corporal William Henry Darby, no 551333, of the Canadian Corps Military Police, died in action at Ypres age 39, on 13 November 1917. He was buried at Nine Elms British Cemetery, Poperinghe.