Hore left Australia on 25 February 1915 as a captain with the 4th Reinforcements for the 8th Australian Light Horse Regiment.

Hore joined the regiment at Gallipoli on 26 May and was wounded at the Battle of the Nek on 7 August.

The Battle of the Nek was a brutal battles at Gallipoli where the Light Horse was almost obliterated in one day.

Hore was promoted to major at Pozières in France and then to lieutenant-colonel. On 18 June 1916, he was awarded the Military Cross for conspicuous gallantry at Pozières.

After the war, Hore moved to New Guinea and worked in the administration and then retired to a plantation in the province of New Ireland, where he remained until his death on 1 September 1935.

Hore was a lawyer working in Hobart when he enlisted.