George Valentine was born c. 1842. Little is known about his early life. By 1880 he was headmaster of a boys' boarding school located at 9 Eliot Place in Blackheath, London. This school employed Montague John Druitt from 1880 to late 1888, when Druitt was dismissed for unknown reasons. It has been suggested that Valentine suspected Druitt of molesting students, though this has never been substantiated. Nothing else is known about Valentine's life. He died c.1912.
Valentine appeared in Eddie Campbell and Alan Moore's From Hell, where he was shown firing Druitt for the alleged sexual molestation which had been fabricated by the Freemasons.