Harry was the son of Ernest Oppenheim and Helen Kate Oppenheim of Leithfield. Ernest was the proprietor of the local pub. He was one of thirteen children, two of whom were born after Harry was killed. He put his age up by a year or so when enlisting. He also recorded that he had previous military experience with E Battery. His employer was Mr Gorrie at Sefton, north of Christchurch.

The fighting in which Oppenheim died took place at Rhenoster Kop about forty miles east of Pretoria. Making their way to Eerste Fabricken, where they spent two days, they came in contact with the Boers on 26 November. They kept up a running fight until 29 November. The description of the action on that day in New Zealanders and the Boer War suggests fierce fighting with high casualties. It reads:

'The first man hit was Farrier-Sergeant Smith (Second Contingent), mortally; then Oppenheim. MacBride carried Oppenheim out of the fire, only to get hit himself. Captain Crawshaw, then dangerously wounded, was attended by Hill, Beath and Foreman dropping. Hill ran to them, and was shot badly through both hips himself. Sergeant Henderson then carried Hill out of the zone of fire. Meanwhile Corporal Stephens was going backwards and forwards carrying ammunition through the rain of bullets.' (p. 90)

An account of the circumstances surrounding Trooper Oppenheimer's death appears in The New Zealand Herald, 3 January 1901.

Originally his grave was at Reitfontein Farm near the battle site at which he died. He is now buried at the Diamond Hill Garden of Remembrance.

Name transcribed as Openneim on the Marker at Diamond Hill for those killed at Rhenoster Kop and reburied at Diamond Hill

Father was named Ernest Oppenheim.

Name incorrectly spelt as Opperheim on South African Roll of Honour at Auckland War Memorial Museum. AWMM