The elder brother of Michael Hobart Seymour, he was the son of John Crossley Seymour, vicar of Caherelly in the Church of Ireland diocese of Cashel, who married Catherine Wight, the eldest daughter of reverend Edward Wight, rector of Meelick, County Limerick, a member of an old Surrey family.
He was born in County Limerick on 19 December 1789, and received most of his education at home. He was drawn in early life to the religious group formed by Selina Hastings, Countess of Huntingdon. About 1850 he went to reside in Italy, and spent many years in Naples.
In 1869 he retired to Bristol, and died there in October 1870.
