He is a grandson of Sir James Granville le Neve King of Campsie, 3rd Baronet (1898 –1989), a nephew of Sir John Christopher King of Campsie, 4th Baronet, and therefore a first cousin of the current Baronet, Sir James Rupert King of Campsie, 5th Baronet.
Born in Bristol, England, Marsden has a degree in anthropology[2] and worked for some years for The Spectator magazine.
He was elected as a Fellow of The Royal Society of Literature in 1996.
[4] A review of his work by Guy Mannes-Abbott appeared in The Independent newspaper in November 2007.
[5] He lives in Cornwall[6] with his wife, the writer Charlotte Hobson,[7] and their children.