Harold Hill was born in 1896 in Brighton, Victoria and was 19 years and 2 months old when he enlisted in Melbourne. On 8 May 1915, Hill boarded the HMAT Euripides in Melbourne and sailed for Egypt as part of 23 Battalion. After landing in Alexandria, the battalion moved to Heliopolis to commence training, then in August set sail for Lemnos and Gallipoli. Hill served at Lone Pine, but did not see any major offensives during his time there. Falling ill in October, Hill was transferred to hospital. By 3 November he was listed as being dangerously ill with pleurisy and bronchial pneumonia. Hill didn't return to duty until February 1916 and in March sailed for service in France. In July, Hill transferred to the 6th Light Trench Mortar Battery, and took part in the battle of Pozieres.
In August 1918, Hill was awarded the Military Medal for action near Herleville, east of Amiens. He was presented with the medal by the The Governor-General, Sir Ronald Craufurd Munro Ferguson at Government House in Melbourne in November 1919, 4 months after his discharge and return to Australia.