His father, Ronald George Elidor Campbell (1848–1879), was the second son of the 2nd Earl Cawdor and an army captain, was killed at the Battle of Hlobane in the Zulu War in 1879.

[1] Campbell was 39 years old, and a temporary lieutenant colonel commanding the 3rd Battalion, Coldstream Guards during the First World War when the following deed took place for which he was awarded the VC.

On 15 September 1916 at Ginchy, France, during the Battle of the Somme, Lieutenant Colonel Campbell took personal command of the third line when the first two waves of his battalion had been decimated by machine-gun and rifle fire.

[5] In 1919 he was appointed aide-de-camp to King George V, a post held until he retired from the army in 1933, and was subsequently a member of the Honourable Corps of Gentlemen at Arms[1] until his death.

In the Second World War he was an honorary flight lieutenant in the Royal Air Force Volunteer Reserve from 1939 to 1940, then from 1941 until his death commanded the 8th Battalion Gloucestershire Home Guard.