The youngest son of the Archbishop of Canterbury, Edward White Benson, and the society hostess Mary Sidgwick Benson, Robert was descended from a very long line of Anglican clergymen. He had also read the litany at his father's 1896 funeral at Canterbury Cathedral and was widely expected to one day take his father's place as the most senior clergyman in the Anglican Communion. After a crisis of faith described in his 1913 memoir "Confessions of a Convert", however, Benson was received into the Roman Catholic Church on September 11, 1903.