A watch given to King Edward VIII by his then lover Wallis Simpson is expected to fetch up to £30,000 at auction.
The onyx pocket watch by Cartier was given to Edward by the socialite in April 1936 – months before his abdication in December of that year.
It is inscribed “Easter 12/2/36” and comes with a suede pouchette by Cartier.
Following his abdication, Edward married Ms Simpson in June 1937 – with the couple then given the titles of the Duke and Duchess of Windsor.
Her main possessions, including many previously owned by the Duke of Windsor, were sold at an auction the following year.
The auction, named the Jewels of the Duchess of Windsor, was held in Geneva and raised more than £30 million.
Some of the auctioned items – including the Cartier watch and a hallmarked pencil holder – are now to be sold by Henry Aldridge and Son in Devizes, Wiltshire.
Auctioneer Andrew Aldridge said: “Edward and Wallis represented one of the most controversial love stories of the 20th century, and the Cartier watch represents a small but important part of that story.
“It was a personal gift from Wallis to Edward in Easter 1936, which was the only Easter he was king.
“Their relationship caused the constitutional crises that resulted in his abdication only months late and this is a tangible piece of history from that time.”
The gold hallmarked pencil holder is expected to fetch up to £7,000, while a gold pocket magnifying glass engraved with the letter E is estimated to sell for a similar amount.
A hallmarked silver gilt writing set is due to fetch up to £30,000.
The items will be auctioned on Saturday.