He was the second son of Walter Long of Corhampton, Hampshire, by Lady Mary, eldest daughter of William Carnegie, 7th Earl of Northesk.
He started studies at Balliol College, Oxford on 5 June 1835, and graduated as a Bachelor of Arts in 1839, and as a Master of Arts in 1844.
He was a justice of the peace for Somerset, and a Fellow of the Society of Antiquaries.
Both had appeared in a shorter form in Wiltshire Archaeological and Natural History Magazine.
He died on 14 April 1886, at Onslow Gardens, London.