Copy of 1939 periodical containing piece by Hitler’s nephew recounting his time with the führer is on sale for over £700

Six yellowing pages headed Why I Hate My Uncle, in a US magazine sold for 10 cents in 1939, have boosted its current value to over £700. The picture byline of a Clark Gable lookalike was of William Patrick Hitler: his uncle was Adolf.

The extraordinary article in Look, then a photojournalism rival to Life magazine, contains striking vignettes of the German dictator in his holiday retreat in the mountains, Berchtesgaden: “Hitler was entertaining some very beautiful women at tea. When he saw us, he strode up slashing a whip as he walked and taking the tops off the flowers. He took that occasion to warn me never again to mention that I was his nephew. Then he returned to his guests, still viciously cracking his whip.”

The magazine, described as having “somewhat above average wear”, is being sold by a dealer in Canada, through AbeBooks, for £730 – “comfortably the most expensive copy of Look listed for sale”, a spokesman for the website said.

The piece is more a ransacking of the family album than weighty journalism. The caption for an autographed photograph of the Führer records: “We had cakes and whipped cream, Hitler’s favourite dessert. I was struck by his intensity, his feminine gestures. There was dandruff on his coat.”

At the time of the article, on the eve of the second world war, the Liverpool-born nephew was in the US with his Irish mother, frantically disengaging himself from the uncle whom he had stayed with, begged for a job, and finally attempted to blackmail, before fleeing Germany when told the price of a good job would be to adopt German citizenship.

His mother, Bridget Dowling, met Hitler’s brother Alois in Dublin. They married in 1910 against her family’s wishes and moved to Liverpool, where William Patrick was born. In 1914 his father deserted the family and moved back to Germany, where he married again bigamously. Their story – and the unproven family anecdote that the young Adolf briefly visited Liverpool – inspired Beryl Bainbridge’s novel Young Adolf, later adapted into the play The Journal of Bridget Hitler.

The nephew’s relationship with Hitler was much more ambivalent than the headline suggested. He first attended a Nazi rally with his father in 1929. He returned to Germany in 1933 and took jobs in a bank and then a car plant through Hitler’s influence. By his account, Hitler then unaccountably turns against him; in fact he had tried to blackmail his uncle, threatening to sell stories to newspapers, and to reveal his “unusual family history” – an implication that Hitler had a Jewish grandfather. In the article, he admits Hitler was furious about the newspaper pieces as early as 1931: “Pacing up and down, wild-eyed and tearful, he made me promise to retract my articles and threatened to kill himself if anything else were written on his private life.”

The article includes a photograph of Hitler chatting with a little girl on a sunny balcony. The caption suggests a darker story: “When I visited Berlin in 1931, the family was in trouble. Geli Raubal, the daughter of Hitler’s and my father’s sister, had committed suicide. Everyone knew that she and Hitler had long been intimate and that she had been expecting a child – a fact which enraged Hitler. His revolver was found by her body.”

His last meeting with Hitler was tricky. “He was in a brutal temper when I arrived. Walking back and forth, brandishing his horsehair whip … He shouted insults at my head as if he were delivering a political oration. My parting with my father was scarcely more pleasant, but his meanness was more understandable since he lives in mortal terror of publicity and knew that I would be free to talk once I left Germany. In February 1939 I sailed for the United States.”

In the US he went on a lecture tour with his mother – who also published a memoir – sponsored by the newspaper tycoon William Randolph Hearst, changed his surname to Stuart-Houston, and served in the US navy during the war. He died in New York state in 1987.