He was the son of Algernon George de Vere Capell, 8th Earl of Essex, and Mary Eveline Stewart Freeman.
He retained his military connections and became Lieutenant-Colonel in 1947 and was commanding officer of the 16th Airborne Division Signals Regiment (Middlesex Yeomanry) (Territorial Army) in 1948.
[citation needed] Capell inherited the Earldom of Essex on the death of his father in 1966 and took his seat in the House of Lords.
[1] In his maiden speech in 1971, he opposed the recommendation of the Roskill Commission for the siting of a third London airport at Cublington.
[5] On his death in 1981, the title became dormant, but it was revived eight years later by a distant cousin, Robert Capell.