"A painting bought by tourist Anna Sheersmith from a young painter in 1908 in Vienna is set to fetch more than £10,000 at auction as it has emerged it was by the then unknown Adolf Hitler.

The picture, brought back as a holiday souvenir, has been unveiled in public for the first time and looks set to fetch at least £10,000 at auction next month. Its story had been kept a family secret for over 100 years, hidden by Mrs Sheersmith's relatives until they entered it into a British auction earlier this year.

"The New Jersey seller, who wishes to remain anonymous, said the picture had been picked up by her great great aunt on her regular trips to Europe. She said her kindly relative could have had little idea what history had in store for its artist.

She said: "Anna used to go every year for a tourist trip to Austria and Germany. She was a great lover of travelling and carried out the same sight-seeing visits every year from 1894 until 1914. As I understand it she always used to bring something back for the family. Obviously one year she had been taken by this painting and bought it and brought it back here."

The five by three inch painting bears the hated Fuhrer's instantly-recognisable signature and its subject matter correspond with Hitler's activities the year it was painted. He was rejected twice by the Academy of Fine Arts Vienna in 1907 and 1908 after being told he was unfit for painting by masters at the school.

Down on his luck he resorted to copying scenes from postcards and selling to merchants and tourists in an effort to raise funds for himself - where Mrs Sheersmith found him.

The painting, which shows a town in the foreground with buildings nestling around a lake, was taken back by her to her home in Cincianatti [sic!]. She then framed it at the city's Barton's Art Store and the picture still bears labelling from the firm, adding to its authenticity."

"It goes under the hammer later next month on October 1 at a Mullocks auction at Ludlow Racecourse in Shropshire. The firm's historical documents expert Richard Westwood-Brookes said the painting would have cost very little at the time it was bought.

He said: "The story behind this is quite incredible, it comes from the era when Hitler was operating in Vienna. Mrs Sheersmith would have only paid a few dollars for it and she probably would have thought nothing of the dishevelled young painter who sold it to her.”

"She would have had no reason to suspect that Hitler was anything more than an impoverished student. This is a piece that has never been seen before outside of the family. I guess the way it was bought is the equivalent of buying some kind of trinket from someone sat at the side of the road in London.”

"It would have been framed and put up on a wall when she returned to America, but the seller found it in quite an ornate box. It looks like it was hidden away once Hitler rose to notoriety - and understandably so."