David Walskovski, an amateur collector, made the winning bid by telephone from his home in Key West, Florida. 'Mr Walskovski met Greta Garbo in 1943 and remained a lifelong fan,' a Sotheby's spokesman said.
Spanning 40 years, the letters from Garbo to the screen writer Salka Viertel offer a valuable insight into one of cinema's most enigmatic figures. They confirm that her desire to be alone extended well beyond the movie star image and create a picture of a reclusive and lonely woman, who found little purpose in life after her decision to retire from movies, aged 37.
In the letters, Garbo's depression seems relentless. In one she writes of her 'terror and utter sadness' and in another she confesses: 'It is sad to be alone but sometimes even more difficult to be with someone.'
Dr Peter Beal, Sotheby's deputy director, said: ' 'I want to be alone' was more than Hollywood hype. I think giving up acting was her biggest mistake and she knew it. For the next 50 years she was simply at a loose end.'
Garbo appears to have spent her time shuttling between her various homes, 'fussing' over apartments that few visited. Her fear of the Press and of being recognised in public verged on paranoia. She refused to stay in hotels and her staff were vigorously vetted. Some of the correspondence deals with elaborate plans to ensure her privacy.
There are few mentions of any social life. Garbo writes: 'I have no lovers but I have troubles all the same.' Later she tells her friend that she has spent three days in her New York apartment without seeing a soul.
Mrs Viertel's novelist son Peter, who sold the letters, has denied allegations that the letters to 'Darling Salka' are evidence of a lesbian love affair between Garbo and his mother, who died in 1978.
Garbo, who never married, does profess her love for Mrs Viertel, who first acted with her in the German version of Anna Christie in 1930. She later contributed to the screenplays of her most celebrated films, including Queen Christina and Anna Karenina. Salka, she writes, is the only thing in Holywood which gives her any delight. In one curious note she confesses her 'great longing for trousers' and asks Mrs Viertel to create a scene in Marie Walewska which would allow her to wear them. But Dr Beal believes the letters reveal no more than warm affection between intimate friends.
The Garbo letters were part of Sotheby's first auction of film and animation art, recognition of the growing market for movie memorabilia. Among more than 500 items was the black lace blouse worn by Marilyn Monroe in Bus Stop, which fetched pounds 5,750. For less affluent Monroe fans, a pair of her stockings and one of her hair combs could be bought for pounds 300 to pounds 400. An outfit worn by Marlene Dietrich in Seven Sinners was also on offer for about pounds 5,000.
'The auction attracts film buffs, historians, producers and those with a passion for a particular star,' Dr Beal said. 'Last year at a Diana Dors auction we had a man who had devoted his life to buying anything to do with her.'
The most expensive lot was a terrifying 20ft-long, 15ft-high monster 'Queen' from Alien 3, expected to fetch as much as pounds 25,000. Dr Beal described it as the 'ideal burglar deterrent'. Perhaps his customers possess less imagination. The Queen was among a number of items which did not sell.