HER story bears an uncanny resemblance to that of Pocahontas, whose adventures were immortalised in the Disney film.

A striking portrait of another princess, who rescued a seventeenth-century Scottish adventurer from imprisonment in Zanzibar in the same era, will

surface at auction for the first time tomorrow.

The extraordinary tale concerns Sir John Henderson, of Fordell Castle, Fife, who

apparently fought in various campaigns in Africa before being captured and held prisoner in Zanzibar in the early 1620s.

An unnamed princess from the island fell in love with him and arranged for their escape by boat to Alexandria, where she fell ill and died.

On his return to Britain,

Henderson married Margaret Mentieth of Randiford in 1625 and had 10 children.

He had a distinguished career as a soldier in England and was knighted by Charles I before being captured after the king's defeat at Marston Moor. He was released on parole and allowed to travel to Denmark, where he had a diplomatic role.

However, he never forgot the ill-fated princess who saved his life and commemorated her by

having her picture painted by an unknown artist, which was in 1731 copied or elaborated on by the portrait artist Walter Frier.

It hung for generations in Fordell Castle, the imposing sixteenth-century home of the Hendersons,three miles west of Aberdour on the edge of a ravine above the the Keithing burn,.

Now a descendant is selling the painting, which shows the dark-haired princess wearing a crown, holding an orb and

posing next to her black maid.

The 25in by 48in canvas, entitled Portrait of the Princess of Zanzibar with an African

attendant, is being offered at Sotheby's in London tomorrow with an estimate of #60,000.

On the back is inscribed: ''John Henderson of Fordell Travelling in his youth thro Several parts of Asia and Africa from ye 1618 to ye 1628 was delivered unto

Slavery by a Barbari Prince in Zanquebar on the Cost of Africa where a Princess of that Countrie contrived to the mians of both their Escape and getting aboard a ship trading up ye Red Sea landed and cam to Alexandrea where she died whose Picture Mr Henderson cauised take with her black Maid . . . ''

The story is related in Sir John Gray's book, Sir John Henderson and the Princess of Zanzibar.

Sotheby's specialist David Moore-Gwyn said: ''This is an almost identical story to that of Pocahontas. The painting is a striking double portrait commemorating a very unusual tale.''

The portrait is said to be based on an earlier portrait but may well be an elaboration of a single portrait of the princess.