Emma Manners, 55, was born in Wales. She became Marchioness of Granby in 1992 on marrying David Manners, the 11th Duke of Rutland, and in 1999 became the Duchess of Rutland.
David, at the time of his marriage, was Marquis of Granby, obviously enough, not Duke of Rutland.
Some of my best friends are Dukes.
I suspect that John Wright didn’t cock up on titles of nobility but simply wrote some execrable English.
Or maybe he thought some aristocrat being named after a pub sounded implausible.
She didn’t become Marchioness of Granby in 1992: she was granted the courtesy title while her father-in-law was still Marquis of Granby