Son of Richard Marquand, director of Return of the Jedi.
Has two sons, Tom and Dan.
James is also an artist and while attending high school in Massachusettes USA won an art prize which was presented to him by US House of Representative for Massachusettes 4th Congressional district Barney Frank.
Both of James's Grandfathers were Labour Party politicians. Hilary Marquand was the minister of health, and Elwyn Jones was the Attorney General and Lord Chancellor.