“SUFFERING” was the first word that came to Maria Altmann when she was asked about Aunt Adele Bloch-Bauer. Frail, dark, beautiful, always with a headache. Children annoyed her, because she had none of her own; small-talk made her furious, because she wanted to discuss religion and politics. (“My darling,” Mrs Altmann would sigh, “Adele was a modern woman living in the world of yesterday.”) Adele smoked like a chimney, and would drift around in loose white gowns with a gold cigarette-holder. Or she would sit, regal in black, holding court for musicians, artists and writers in the salon of her huge house just by the Vienna Staatsoper.

But the Adele the world came to know was as Gustav Klimt had painted her in 1907. It took him four years, longer than he spent on any other painting. He placed her in a swirling gown within a blaze of gold rectangles, spirals and Egyptian symbols from which she looked out in nervous loveliness, the epitome of Vienna's Golden Age. Her hands were strangely bent because, Mrs Altmann knew, she had a crippled finger, which she always tried to hide. She was also fairly sure that Aunt Adele and Klimt, with his satyr face and wild sexuality, had had a mad affair; her mother angrily denied it, said it had been just “an intellectual thing”, but you only had to look at her aunt's dark, languorous, faintly smiling eyes to think otherwise.

“Golden Adele” haunted Mrs Altmann for the rest of her days. As a girl she led much the same “beautiful” life, dressed up in silk and organza, in a stately townhouse nearby, where artists and philosophers came and went to the sound of her father playing on a Stradivarius cello. After 1925, when Adele died at 43, the regular Sunday brunch at Uncle Ferdinand's would always include a viewing of the Klimt portrait, hung in Adele's bedroom in a sweet haze of fresh flowers. Four other Klimts also hung there. Three were landscapes: a beechwood, a dappled apple tree, houses by a river. The other was a later painting of Adele, pale and strained, standing in a big hat with her arms loose amid fauve colours of red, mauve and green.

All five paintings were stolen when the Nazis took Austria over in 1938. Mrs Altmann remembered the jubilation of the Anschluss, the church bells ringing; only the Jews wept. By then, she was just married to Fritz Altmann; and she sometimes wore, next to her skin, some of Adele's diamonds, which Uncle Ferdinand had given her as a wedding present. The Nazis stole them in short order, as they also seized Ferdinand's entire art collection, his delicate porcelain and his sugar refinery. “Portrait of Adele Bloch-Bauer I”, became the symbol of all that the family had lost.

For many years—after she had fled to America with Fritz and made a new life in California, he working at Lockheed, she selling cashmere—Mrs Altmann supposed that the Klimt paintings had legitimately ended up in the Austrian National Gallery. But when the law changed in 1998, in favour of restitution, she vowed to get them back. The Austrian government refused. Adele's will, they said, had given the paintings to the gallery. And, they might have added, all Austria now thought it owned her golden, Klimtian beauty.

Battling in cashmere

Mrs Altmann went to war. At 82, in cashmere and silk scarves, she made an unlikely fighter. Her dress boutique in Cheviot Hills, where clients sat in her living room drinking Kaffee mit Schlag and nibbling on sausage, was probably the last vestige of a Viennese salon in the New World. Golden Adele, in paperweight form, lay on the coffee table and was rubbed hard for luck. But Mrs Altmann was all persistence, charm and energy—and the law was on her side.

Adele's will, as it turned out, only made a “kind request” to her husband to leave the paintings to the gallery. It was not binding, and in any case Mrs Altmann knew Adele's mind. She wanted the paintings left to the Vienna she knew, the vibrant, glittering, tolerant city of the early 20th century; not to a place from which all Jewish life had gone. She would never have felt at home there, as Mrs Altmann no longer did when she visited, defying security guards at the National Gallery to be photographed beside Aunt Adele, and saying loudly: “That painting belongs to me.”

In 1999 she and her lawyer, Randol Schoenberg, tried to sue the Austrian government. When that proved too expensive, they argued as far as the Supreme Court that the case should be heard in America. They won; but then, in 2004, they went to independent arbitration. Three Austrian academics decided that the paintings should be returned. In 2006 Aunt Adele and the rest arrived with fanfare in Los Angeles: the largest single return, in monetary terms, of Nazi-looted art.

Only a few months later they were sold. All but one went away to private houses. The exception was Aunt Adele. She had always wanted her golden portrait in a public gallery, Mrs Altmann said, and so it was “beautiful” that Ronald Lauder, a businessman and philanthropist who had loved Adele's face from boyhood, instantly paid $135m to enshrine her in his Neue Galerie in Manhattan. Of course, she was too far away for many visits now. But Mrs Altmann could imagine her there, glowing and frail, wearing just the faintest aroma of those long-vanished cigarettes.