Serving in the army he arrived at Mudros on the 14th July 1915 on his way to Gallipoli with the 6th battalion of the East Yorkshire Regiment., landing at Suvla Bay on the 7th August 1915. He was shot through the head behind the eyes at Suvla Bay, but amazingly recovered and was sent to the front again. The Battalion distinguished itself amid the hopeless muddles of General Ian Hamilton and his Staff. At the time of his death Horace was in the 7th Battalion of the Regiment and was Bombing Officer at a Midland Camp in England when a grenade, thrown by a private soldier, exploded prematurely. Both were seriously injured "but Captain Willats first and last thoughts before he succumbed to his injuries were for the young private". He is buried in Grave 79.40479 in the Highgate Cemetery, St. Pancras in north London.