THE author of the Outlander books has claimed that use of the term "Scotch" was popular in Scotland until the SNP came into power. 

Many are questioning the historical accuracy of a tweet by Diana Gabaldon in which she said that "everyone" used the term "Scotch" until "the SNP got into power in the mid-20th c".

The American author of the hugely successful fantasy books was responding to a fan who asked what kind of hat the character Jamie, played by Scottish actor Sam Heughan, was wearing during a scene from the television series Outlander. 

The fan said: "The hat he’s wearing as he looks up at Claire. To me it looks like something out of Peaky Blinders. Could be wrong. I remember Charles 3 wearing one shooting grouse in Scotland." 

Gabaldon said the hat was a "Scotch bonnet". 

"If you mean the ghost, he's wearing a Scotch bonnet (yes, I do mean Scotch) with a feather in it – very traditional (hence the "Scotch" – EVERYONE (including all the Scots) used that term until the SNP got into power in the mid-20th c.)" 

Many have pointed out that the SNP did not get "into power" in the mid-20th century (the Scottish Parliament was not reconvened until 1999). 

However, a professor of Scottish history has also cast doubt on Gabaldon's claims about the usage of the word "Scotch". 

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Ewen Cameron, a professor Scottish history and palaeography at the University of Edinburgh, told The National: "A Scotch Bonnet is a mushroom!

"I think she's completely wrong about this, the word Scotch, which probably emerged in usage in the 17th century, was mostly used by outsiders to describe the Scots.

"By the mid-19th century it was going out of fashion and by the 20th century, long before the foundation of the SNP far less its ascent to power, it was seen as archaic and perhaps even mildly insulting." 

Diana Gabaldon has been contacted for comment.