At the time of the Great War, Harry's family home was at Branston, Mellor, Derbyshire . His mother, Hannah, lived there but it is not known if her husband, John, had died by that time. He had certainly died by the early 1920s. Harry was their youngest son.
Nothing is known for certain about Harry's private life but his commemoration on the Stockport War Memorial suggests that he may have worked in the town. He is also commemorated on the Memorial in Mellor. He enlisted into the army, as a private, joining one of the Royal Fusiliers "Public Schools Battalions" with an original service number of PS/4284. This choice of unit confirms that Harry came from a comfortable middle class family.
He received his commission into the Cheshires in October 1916 and, unlike many of his officer colleagues, he did not receive further quick promotion even though casualties amongst the officers were high. It was not until 26 March 1918 that he was promoted from 2nd Lieutenant to Lieutenant. It would seem that he was in Britain at this time as his newspaper obituary refers to him going overseas "for the third time" on 22 June 1918.
On 16 July 1918, the Battalion was at a position known as Mont Rouge near the Belgian village of Locre (now Loker), some 11 kilometres to the south west of Ypres (Ieper). The Battalion's War Diary records what happened:-
"The day opened with a heavy thunderstorm and later, enemy shells landed near Brigade HQ> This shelling continued all day. From about 7.30pm onwards, the roads behind our position were shelled with gas shells. Working parties were found by all Companies. Just as they were on the point of setting out, the enemy put a burst of 15mm shell on the road near Brigade HQ, killing Lt H A Wainwright and 4 Other Ranks, and wounding 13 others."
The Commanding Officer, Colonel Hodson, wrote to Harry's parents "It is with deep regret that I have to let you know that your son was killed last night. He was to take his men along a certain road and before risking them, he very properly decided to reconnoitre the way first. In doing so, he was hit by a piece of shrapnel and killed instantly. His soldierly instinct in going ahead first undoubtedly preserved the lives of many of his men. I knew your son when he was with the Battalion last year and was delighted to welcome him back again. It is very hard that he should be killed o soon after his return."
One of the Other Ranks to be killed was Frank Liveley and they are buried together at Abeele Cemetery. Fred Irwin was badly wounded and died two days later.
After the War, Mrs Wainwright had moved to Hillmorton Paddox, Rugby. She called her new home "Abeele" after the Cemetery where Harry is buried.