MANY clan tartans worn proudly by Scots are not the ancient traditional colours of their ancestors but a stroke of marketing genius by two 19th-century English brothers, according to experts.

Scots all over the world wear the kilt and other items in a family or clan tartan.

However, a BBC Scotland documentary shown tonight says many were simply invented by John Carter Allen and Charles Manning Allen.

The English brothers changed their name to Sobieski Stuart and claimed descent from Bonnie Prince Charlie. They claimed to have found a manuscript called the "Vestiarium Scoticum" – or wardrobe of the Scots – which listed 75 tartans connected with certain clans back to the 1580s.

But many still worn today were fakes. Speaking in Spinning a Yarn: The Dubious History of Scottish Tartan, Brian Wilton, director of the Scottish Tartans Authority, says: "Vestiarium Scoticum was a brilliant work by the Sobieski Stuarts. Most of it is false but we don't know which bits.

"They produced beautiful tartan designs and even allocated tartans to families, particularly down in the Scottish Borders, who'd never had a tartan before."

Professor Murray Pittock, of Glasgow University, said: "It's the creation of a charismatic textile by a process of fictionalisation."

Spinning a Yarn: The Dubious History of Scottish Tartan is on BBC2 tonight at 9pm