Henry Carson was a surgical bootmaker, aged 27 years old when he enlisted on 12 July, 1915. He was a married man and he and his wife, Susan, lived at 23 George Street, East Melbourne. He had some previous experience, having been in the Cadets at school. He was attached to the 6th Depot Battalion for training from 12 July to 16 Septemeber. After training, he was placed with the 6th Battalion, 12-20 Reinforcements nad left for Egypt on board HMAT Nestor A71 on 10 November, 1915. 

On 24 January, 1916, he was promoted to Corporal and discharged to duty from the 3rd Auxiliary Hospital at Cairo. It is not clear whether he was ill or whether he was following his trade. With so many wounded at Gallipoli, it would not be surprising if a surgical bootmaker was a useful person to have at a hospital.

On 3 March, 1916, he was taken on strength with the 6th Battalion at Serapeum. The 6th Battalion was severely depleted, having taken part in the ANZAC landing, then the battle of Lone Pine and then the attack on Krithia, where it lost one-third of its strength. They stayed n training in Egypt until March, when Henry Carson and other reinforcements joined them, before sailing for France. In July, 1916, they were n the front lines at Pozieres. It was here that Henry Carson won his Distinguished Conduct Medal 'for conspicuous and consisten gallantry during operations' while he was Officer in Comman of the 1st Pioneer Battalion. The full citation is worth recording and covers the period from 15-22 August:

At Pozieres, France, 15-22 August, Sergeant CARSON was daily in charge of parties constructing and consolidating. He showed much courage in cutting 1st Avenue, continuing to work with his party during a successful attack by British troops in close vicinity in spite of enemy fire. Again, in constructing the trench near MOUQUET FARM from RATION TRENCH his conduct was most conspicuous. Early in the night he was buried by debrisa from the explosion of an enemy shell and after a short rest recommenced work. Later the same night he and two others were buried but a second time after a spell he returned to work which was successfully carried out. His example and work were a great encouragement to his men.

By then Henry Carson had the rank of Temporary Sergeant, having been promoted following the evacuation on 1 August of his wounded superior, Sergeant Blackburn. On 25 October, the promotion was made permanent. By 18 October, he was a 2nd Lieutenant. he was given leave to the UK on 22 December, 1917, rejoining his battalion on 5 January, 1918. He returned to England from France on 1 February, and on 2 February, was seconded for duty at Sutton Veny. In June, he was ill, and spent four days in hospital, returning then to Sutton Veny and on 26 June, was given the rank of Warrant Officer.

He returned to Australia on Board the HMS Sondham on 12 May, 1919, and was struck off strength on 19 October that year. his name had been registered in the Census as living at 23 George St., East Melbourne, throughout the war, but in 1924, he moved to Alphington with his wife, Susan. He was working as a salesman and they lived at 18 Langridge St., where they stayed until 1936In 1937, Henry Carson listed himself as a manager and he, Susan, and their daughter, Susan junior, were at 12 Bruce St., Brighton. The last entry in the Census is for 1942, when they were still in Brighton.