From the moment that Mel Gibson’s William Wallace — in blue and white facepaint and a tartan kilt — charged the English with the cry of “They can take our lives but they will never take our freedom”, historians have lined up to point out that, actually, Wallace was not the poor villager depicted in Braveheart, but a landowner and minor knight.

Now, 15 years on from filming, Gibson has conceded that the film played fast and loose with the historical truth — and that Wallace was “a monster” who was recast as the good guy for the sake of Hollywood convention.

Yet the star’s admission has done little to appease historians, who have claimed that Wallace’s real character probably fell somewhere inbetween.

Gibson, who also directed the 13th-century epic, spoke out in an interview to mark 15 years since its release. He said: "Wallace was a monster. He always smelt of smoke; he was always burning people’s villages down. He was like what the Vikings called ‘a berserker’.

“He wasn’t as nice as the character we saw up there on the screen. We romanticised him a bit. We shifted the balance because someone’s got to be the good guy against the bad guy; that’s the way stories are told.”

Dr Fiona Watson, a Wallace biographer and former University of Stirling academic, said that Gibson’s new position was fascinating. “After 15 years, Mel Gibson’s giving us the other version of the myth, the knuckles dragging across the floor one, which is equally untrue,” she said.

“The real man surely lies in between. After all, Wallace went to the Continent on diplomatic missions after the debacle at Falkirk (the 1298 battle), which Wallace lost. I don’t know of many berserkers who did that.”

She added: “And if we’re looking for uncivilised behaviour in that period then Wallace is not the only one indulging in it — Edward I of England was surely at least as bad, if not worse.”

Despite the film’s commercial and critical success — it won five Oscars, including those for Best Film and Best Director — Braveheart was described by some as “Jocksploitation”. Commentators said that it created a second Brigadoon: a fantasy Scotland based on lies. The areas of artistic interpretation include Wallace’s love affair with Queen Isabella. She would have been aged 2 at the time.

And the errors extend beyond the script to the wardrobe department. The kilts, which were worn by all Scots on the screen, were not invented for another three centuries. The historian Sharon L. Krossa likened it to “a film about Colonial America showing the colonial men wearing 20th-century business suits”.

Randall Wallace, the screenwriter, has defended his script against such onslaughts. He has said that it was based more on the earliest account of Wallace’s death, by the minstrel Blind Harry, than on any historical source. “Is Blind Harry true? I don’t know,” he said. “I know that it spoke to my heart and that’s what matters to me.”

Braveheart was also adopted by many Scottish Nationalists as a rallying call for independence, a move that Gibson said he had not given permission for. Leaflets distributed at cinemas when the film was released — pre-devolution — read: “Independence isn’t just history. Most European nations have it. Scotland needs it again and now almost 40 per cent of the Scottish people agree. Most of them vote SNP.”

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