Through his grandmother Lord Barnard is a direct descendant of the Nevills of Raby.
The llth Baron served as a flying officer with the R.A.F.V.R.I from 1942-46. From 1948-66 he was affiliated with the Northumberland Hussars (TA) acting as Lt. Col. commanding from 1964-66. Lord Barnard was Lord Lieutenant of the County of Durham and Custos Rotulorum from 1970-88. From 1979-89 he was Hon Col. of the 7th (Durham) Battalion the Light Infantry.
Lord Barnard is actively involved in conservation projects connected with the environment on the Estate and is Vice President of the Game and Wildlife Conservation Trust. He has also been an Hon. Vice President of the British Red Cross since 1999.
In 1952, Lord Barnard married Lady Davina Cecil, daughter of the 6th Marquess of Exeter. In addition to the heir, Henry Frances Cecil, they have four daughters - Carolyn Mary, Elizabeth Anne, Sophia Rosalind and Louise Cecily.
Henry married Lydia Katherine Robson in 1998 and they have two daughters and one son: Cicely Margaret, Alice Isabella and William Henry Cecil.