While he is undoubtedly showing his age, experts believe the cat, discovered in the foundations of Woburn Abbey, is by far the best preserved example they have seen.
Tradition once decreed that good rat catchers were buried in foundations to protect the house after their death and across the capital similar mummies remain interred beneath houses.
"It is very likely that the cat was one of the estate mousers, and was probably a very good one. It was buried in the foundations to protect the building against rodents and infestation," explained Richard Sabin, curator of mammals at the Natural History Museum.
The museum found one cat under its own entrance and another was discovered during renovations on a Georgian house in Knightsbridge. "The owner was pretty shocked when he was told about it, and brought the mummy in to us," Mr Sabin said.
But, true to aristocratic form, the duke's moggy was so well preserved in an airtight brick container beneath the Bedfordshire abbey - free from humidity, predators and bacteria - that even his whiskers are still intact. "It's by far the best preserved cat we have ever found in Britain," the curator said. Originally discovered in 1915 by workers demolishing an outhouse, the duke's cat will go on show for the first time next week in an exhibition at the National History Museum's Walter Rothschild Zoological Museum in Tring, Hertfordshire.
It is one of many mummified creatures including a baboon, a crocodile and birds of prey which will go on display from Monday. A tawny owl which was found behind a panelled wall at Hampton Court and a grey squirrel discovered in a cottage loft are two other examples of animals mummified in the United Kingdom which will be on show.
The museum will also display an array of Egyptian mummified animals and explore the reasons why the ancient civilisation practised such an art.
Cats, monkeys and even gazelles have been found buried alongside their owners and pet cats sometimes received their own elaborate burials, complete with cat-shaped coffins.
Mr Sabin added: "We've discovered some bizarre things about ancient Egyptian culture. Through X-ray examination of some of our wrapped cat mummies we've discovered that many appear to have had their necks deliberately broken.
"This suggests that cats may have been killed to meet the demand for them as high-status ritual tomb deposits."
Through studying animal mummies, scientists and archaeologists have been able to learn more about their role in ancient Egyptian society and their identification with particular gods, as well as the process of domestication, primarily in cats and cattle.Reuse content