Charles was born in Bristol, the son of Col. Charles Edward Duff, C.B and his wife Mary Emily Slaughter. Col. Duff had commanded the 8th King’s Royal Irish Hussars from 1901 until he retired on half pay, in 1905. The Duffs lived in Bradford Abbas, Dorset for many years. and their daughter was born there in 1913.

Charles was educated at Eton and came up to Christ Church in 1924. After taking his degree in 1927, he joined the army.

The Christ Church record gives his address in 1937 as 8th King’s Royal. Irish Hussars, Egypt. The regiment had helped quell civil unrest in Palestine in 1936 and had returned to Egypt as part of the Matruh Mobile Force.

In the same year, he married Celia Eleanora Tennant of Harrogate, in Westminster. They had a son and a daughter.

Charles died of wounds on 24 November 1941.

During the three-day Battle of Sidi Rezegh Airfield, the regiment had formed a box leaguer for the night time lull in fighting with the rest of the brigade on 22 November (as neither side had night vision aids, battle normally ceased at dusk). The leaguer was discovered by the 15th Panzer Division during the night, and in the ensuing engagement left the Irish Hussars with just four Stuart Tanks fit for battle; 35 having been captured or destroyed.

He is commemorated on the Alamein Memorial Column 17 and on the Memorial Plaque at All Saints Church, Spofforth and on the Memorial at the Royal Military Chapel, Sandhurst.

His wife remarried in 1951 and died in 1989.