The new exhibition is on display in the East Corridor of Longleat House until 4 June and also features the magnificent 19th Longleat State Chariot used by successive Marquesses of Bath to attend State occasions, including coronations.
The chariot was built by Barker & Co of London in about 1820 with a state-of-the-art suspension system and features heavily padded seating covered with luxurious corded silk.
It was last used by Henry Thynne, 6th Marquess of Bath for the 1953 coronation of Queen Elizabeth II, despite official attempts to persuade him to travel by car not carriage.
On the day of the Coronation, dray horses and a driver from a Birmingham brewery were enlisted to get the Marquess to Westminster Abbey on time.
The ornate coronation robes, which have not been on public display for more than a decade, were created for Thomas Thynne, 5th Marquess of Bath to wear to the coronation of King George VI in 1937.
The 6th Marquess later wore them to the coronation of Queen Elizabeth II in 1953.
The robes are made of sumptuous crimson velvet lined with silk, with a white ermine collar and white silk satin ribbon ties.
The recently restored coronet consists of a circlet of four gold strawberry leaves alternating with four silver balls. It has an ermine band around the base and a crimson velvet lining topped with a gold tassel.
“The coronation of King Charles III presents a wonderful opportunity to display these historic pieces of ceremonial dress worn by Marquesses of Bath to past coronations,” said Longleat House curator Dr James Ford.
“Along with the magnificent Longleat State Chariot, they demonstrate the pomp and pageantry that surrounds these incredibly important national events, and which we as a nation do so well,” he added.
Ceremonial dress for members of the peerage dates back to 1400s, but became standardised by 1700. There are two types of ceremonial robes: parliamentary robes and coronation robes.
The design of the coronation robes and coronet varies depending on the wearer’s rank, either duke, marquess, earl, viscount or baron, which is indicated by the number of strawberry leaves and pearls on the coronet, and the number of lines of black spots on the collar of the robe.
However, it is unlikely that such items will be seen at King Charles III coronation on 6 May. As part of an attempt to simplify the event, the small number of peers attending have been asked to wear business attire or parliamentary robes instead of coronation robes and coronet.