William Ryan was born in Wagga Wagga, New South Wales, was single and a Labourer when he enlisted in the 21st Battalion, 2nd Reinforcement on 21 June 1915 at the age of 18. His unit embarked from Melbourne, Victoria, on board HMAT A64 Demosthenes on 16 July 1915. He proceeded to join the forces at Gallipoli on 30 August 1915 before reporting to hospital as sick (undefined), re-joining his unit on 10 November. On 23 March 1916 he embarked for France from England and was later wounded in action (shell shock) on or about 30 July 1916. After recovering in hospital and re-joining his unit on 10 August 1916 he was again wounded in action just two weeks later. During recovery he developed abscesses and was admitted to General Hospital in Tunbridge Wells, England, for treatment. He was discharged from hospital and granted furlough. It seems he had some issues with overstaying his leave, resulting in numerous offenses listed for being absent without leave (AWL). He left England for Australia on 23 July 1919 aboard the Hospital Transport Main, disembarking at Melbourne on 11 October 1919.

He married Ms. Nellie Lily Violet Reavell of Catford on 12 July 1918. Both were 21 at the time.
Tree No. 750