Now a new biography of Walt Disney has cast a fresh light on one of the most elusive characters of modern American history. The picture that has emerged is far from the genial figure of legend. Disney has emerged as a troubled man, a lonely and reclusive depressive. He also notoriously ill-treated his staff and close friends and was a ferociously right-wing anti-communist during the Forties and Fifties.

The book, Walt Disney: The Triumph of the American Imagination, was written by Neal Gabler, who received unprecedented access to records about Disney. He is the first author to get the Disney family's permission to examine fully the complete Disney archives. Gabler portrays Disney as the emotionally driven son of a cold father who sought to create a fantasy world for himself in which he would feel loved and safe, and ended up spreading that invention to the world. 'During a peripatetic childhood of material and emotional deprivation, at least as he remembered it, he began drawing and retreating into these imaginative worlds,' Gabler writes.

Yet those personal worlds would shape much of modern America and far beyond through characters such as Mickey Mouse, films such as Snow White and eventually theme parks. The figures alone show the astonishing reach of Disney. By the time he died in 1966 more than 240 million people had seen a Disney film, 80 million had read a Disney book and 100 million had watched a Disney TV show. Pop culture experts see Disney's influence as unrivalled. 'He was the dominant culture of childhood for such a long time. He was making a product on a massive industrial scale. It just happened that this product was part of the culture industry,' says Professor Bob Thompson of Syracuse University in upstate New York.

Thompson says it is unrealistic to imagine that the real Disney would match the public image he created. Certainly Gabler's book dispels many of the kindly old man images. He details an at times tragic life. Disney's father ended up resenting his son and their relationship fell apart. Disney refused to cut short a business trip when his father died and missed his funeral. He also had a mental breakdown in 1931 as he and his wife struggled to have children and she suffered several miscarriages. Disney was also cruel and controlling to employees, terrorising them with humiliating dressing-downs. It included even his brother Roy, who kept the company afloat with a financial acumen Walt did not appear to possess. Yet that did not stop Disney from ridiculing Roy in public. At one meeting, discussing the film Fantasia's soundtrack, Roy suggested using some more popular music. Disney kicked him out of the room, saying: 'Go back down and keep the books.'

Disney had a ferocious temper, especially against people he saw as left-wing. He testified enthusiastically before the House UnAmerican Activities Committee and detailed what he saw as communist plots to take over Hollywood. He branded some former animators communists, said the Screen Actors Guild was a communist front and labelled a 1941 strike that hit his studio a communist plot. He even contacted the FBI about alleged communist infiltration.

When his cartoonists tried to form a union, he brought in armed guards. He fired organisers, cut wages and slashed the opening hours of the studio coffee shop. At one point, faced with a strike picket, Disney had to be physically restrained from attacking the leader of the industrial action.

But it was in his private life that the most disturbing images of Disney emerge. In fact, Disney himself felt trapped by his creation and public image. 'I'm not Walt Disney any more. Walt Disney is a thing. It's grown to be a whole different meaning than just one man,' he once complained.

He was in effect married to his studio, ignoring his long-suffering wife. He would retreat into his mansion and play with a huge toy train set with a track that ran for an astonishing half a mile in length, including a 90ft-long tunnel. He also associated with a group of anti-semitic members of the Motion Picture Alliance and frowned on the idea of hiring black people to work in Disneyland.

But Gabler says his prejudices were no different from those of many of his contemporaries and also explodes the urban myth that Disney was cryogenically frozen on his death. In fact, he was cremated and his ashes buried in a private garden. But there is little doubt that his cultural legacy has achieved immortality in a way that the real-life cantankerous and lonely man could not.