KING Charles has appointed his wife Queen Camilla to the "greatest order of chivalry in Scotland", the Order of the Thistle.

Buckingham Palace said that Charles had been "graciously pleased" to hand the order to his spouse.

What is the 'Most Ancient and Most Noble Order of the Thistle'?

The Order of the Thistle is the highest honour in Scotland, and across the UK its prestige is second only to the English Order of the Garter, according to the royal family's website.

The order comprises sixteen knights or ladies and the monarch is the Sovereign of the Order, so any appointments are his "personal gift".

The royal family website further states that The Order of the Thistle recognises "Scottish men and women who have held public office or who have contributed in a particular way to national life".

However, Camilla was born in London.

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William, the “Prince of Wales” and “Duke of Rothesay”, is also in the order, as is Princess Anne.

There are various other peers and members of the aristocracy in the order, such as Richard Scott, the “Duke of Buccleuch”, and David Ogilvy, the “Earl of Airlie”.

Other names in the order include SNP politician and former Holyrood presiding officer George Reid and Elish Angiolini, the former lord advocate of Scotland.

The Order of the Thistle was formally established with a statutory foundation under the rule of Scotland's James VII in 1687. He claimed he was "reviving and restoring" an older order.

According to legend, the order dates back to the year 809AD, but it is possible that it was actually founded by Scots King James III (1488-1513), who was "responsible for changes in royal symbolism in Scotland, including the adoption of the thistle as the royal plant badge", according to the royal family website.

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The Royal Family website further notes Camilla's "work in Scotland" alongside her appointment, stating that she was appointed chancellor of the University of Aberdeen in 2013 and has been a patron of Scottish charities such as the Edinburgh-founded Maggie’s Cancer Care Centres.

The Queen has also "supported" King Charles in visits across Scotland including for COP26, the Glasgow Commonwealth Games, and the opening of the Scottish Parliament.