Historical revisions sparked by the discovery of the remains of Richard III should also prompt a review of the reign of Scottish king Macbeth, an MSP has suggested.
Richard III and Macbeth were both portrayed as villains by renowned playwright William Shakespeare, but the discovery of Richard III's twisted and battle-scarred remains beneath a Leicester car park has led some experts to suggest he was unfairly maligned.
He said: "The discovery of what are believed to be the remains of Richard III has sparked fierce debate about the nature of his reign, especially because of his portrayal by Shakespeare.
"This has strong parallels with the situation in Scotland where Macbeth's reign is characterised by Shakespeare as being one of murder and paranoia, but of course the reality is very different.
"The arts can engender an interest in the past, but they should never act as a substitute for knowledge of actual events. In modern parlance, it's like suggesting people should learn about medieval Scottish history by watching Braveheart."
He added: "In striking contrast to Shakespeare's version of events, we know that Macbeth not only had a long reign in comparison to many monarchs of the time, but his throne was secure enough to allow him to go on pilgrimage to Rome; an arduous trip at the time that some subsequent monarchs might not have risked for fear of being deposed in their absence.
"I am of the strong belief that the coverage of Richard III should act as a catalyst here to right the wrongs about the reign of Macbeth. It is ironic that he remains an iconic monarch to this day largely because of Shakespeare, but I would rather he was iconic on the basis of facts rather than fiction."
Mr Johnstone has tabled a motion in the Scottish Parliament arguing that Shakespeare's Macbeth "is arguably more a reflection on the relationship between Shakespeare and his patron, King James VI, rather than an attempt at historical accuracy".
He said a review of his reign could increase awareness of Macbeth and the Scottish history of the period, and boost visitor numbers to associated sites such as Lumphanan in Aberdeenshire and Glamis in Angus.