A modern-day killing spree rocked the ancient Kingdom of Nepal lastyear. But why did the prince slaughter his family and take his own life? And what about the womanhe loved? A new book tries to solve themystery.......................................... Rana has refused to discuss whatthey spoke of. But shortly after their phone call, Dipendra seemed as if hewas drunk, and was taken to his room, apparently unconscious.........................

Enclosed in a jagged bowl of mountains, the Kingdom of Nepal was for centuries one of the most arcane countries. Featuring the world's highest mountain, Nepal was always going to have romantic associations, but these are compounded by the fact that it has never been conquered or occupied by a foreign country. In these circumstances, the traditions of its royal family remained in the ancien régime style. In addition, the Nepalese king is believed to be a living god, and thus protector of all his people.

In Kathmandu last June, at a regular extended family get-together in the royal apartments, the modern world collided savagely with the ancient. In the billiards room where they had gathered, to chat and have drinks, bodyguards were for once absent, since this was a strictly private event, and being held in the most secure part of the palace. Secure from outsiders, that is, but not from insiders.

That evening, using a sub-machine gun and an assault rifle, 29-year-old Crown Prince Diprendra murdered his father, mother, both his siblings, three aunts, an uncle and other family members. He then shot himself, dying two days later. It evoked both the Romanov assassinations and the modern-day seemingly random killing sprees in places that will now be unhappily associated with them: Dunblane, Columbine and Hungerford. But why did the man who would one day have been king cause such horrific bloodshed of his own family?

English writer Jonathan Gregson has tried to answer this question in his book, Blood Against the Snows; the Tragic Story of Nepal's Royal Dynasty. Gregson was born in 1953 in Calcutta, where his father was an engineer. In the British tradition, he was dispatched to boarding school in Britain when he was eight, returning only for holidays, but his memories of Asia remained strong. He visited Kathmandu with his family in 1964.

"The rice fields came up to the edge of the old city then," he remembers. "The air was completely clean and smelt of wood-smoke. Lots of the big hotels of today were still private residences. It was a place that always struck me as completely different to anywhere else."

Gregson has returned to Nepal regularly since, still going at least once a year. In 1999, while researching a book, Kingdoms Beyond the Clouds, about Himalayan kingdoms, he was granted a rare interview (for a Westerner) with King Birendra.

"I interviewed him in the palace. It was supposed to be 45 minutes, but it ended up being an hour-and-a-half. It was a bit of an Alice in Wonderland experience, because he couldn't give an opinion on anything, in case it would be politically interpreted. So he kept saying, 'On the one hand . . .' and then 'But on the other hand . . .' He was a gentleman. I could see the protocol under which they all lived their lives. Quite frankly, it would have driven me mad if I'd lived there."

Gregson makes this last comment without irony, but there has to be some truth in it. Whatever motivated Prince Dipendra to kill his family, it is unequivocally clear that his was not a normal act. Something in his background, or in his psyche, made him do it, and it's impossible not to examine the context of his life for clues.

At eight, the crown prince was given his first pistol. At 15, he went to Eton, where he kept a loaded revolver.

He went to university in Kathmandu, and then began to be prepared for his future duties as king. By then, he had a private arsenal, but this was not considered unusual, as all royal males carried firearms.

Dipendra passed his 20s in a period when the function of the Nepalese royal family was undergoing great change. The transition to democracy in 1990 meant that the Royal Palace no longer governed Nepal, although they retained their titles and symbolic positions. As Gregson points out in his book: "Internal matters acquired an artificially exaggerated importance. It became a claustrophobic world, heavily laden with petty intrigue: which may explain why Crown Prince Dipendra was forever trying to cut loose from it all."

The question of who Dipendra would marry hung over him throughout his 20s. His sister, Princess Shruti, five years his junior, had already wed. Hers was an arranged marriage, but it was apparently a happy one. Dipendra fell in love with Devyani Rana, whom his seniors in the royal family did not approve of as a future queen. If he married her, he would be marrying outside his clan and caste: to Dipendra, this did not mean a great deal, but to the incumbent king and queen, it meant the difference between a suitable bride and an unsuitable one. Devyani Rana was, they insisted, not suitable at all.

"It was a generational conflict: his parents thought marriages should be arranged, he didn't," Gregson says. "All those things were intensified and heightened because of the background." Marriage was not the only thing they had a control over: aged 29, Dipendra still had to hide the fact he was a smoker from his parents, although he had smoked since his teens.

In June last year, Dipendra's 30th birthday was coming up, and it was perceived as a special marker in his life. The family felt he ought to be married in his 30th year - to one of the two girls they had picked. There was a choice: submission or rebellion, although in truth, rebellion had never previously been a realistic option.

Gregson reconstructs the June 1st evening in the Kathmandu palace last year, using the testimony of some of those who survived. Devyani Rana was not present, since it was a family-only occasion. But she and the prince spoke by mobile phone at the beginning of the evening. To this day, Rana has refused to discuss what they spoke of. What is known, is that shortly after that phone call, Dipendra seemed as if he was drunk, and had to be removed to his bedroom, apparently unconscious.

He emerged from his bedroom only minutes later, having changed into military fatigues and carrying his sub-machine gun. He shot the king first, and while everyone panicked, shot dead his uncle, his sister, brother, three aunts, his mother, and two others. He then shot himself.

It was all over in three minutes, and the citizens of Nepal walking past the palace outside assumed the gun-fire was part of routine target practice.

It was two days before Dipendra died, so Nepal went through the bizarre ritual of crowning its killer king. It was clearly a relief when he died, but the Nepalese people, who were given only sketchy information initially, suspected other parties were behind the shooting, and that the police were conveniently blaming it on a dead man. All this was against the background of ongoing Maoist unrest.

Gyanendra, the murdered king's brother, who survived that night, is now King of Nepal.

"Nepal is in full-scale civil war right now," observes Gregson. "In five or 10 years, there may not be a monarchy any more, depending on the outcome of the conflict."

Devyani Rana fled the country immediately, and remains in exile. She is keeping a low profile in London, where journalists from all over the world are trying to persuade her to tell her story. She is aware of Gregson's book.

"Lots of things in Nepal are done through third parties," he says. "She knows if she talks to the press, that would set everything back for her. And she wants to go back to her family in Nepal . . . if she talked, it could be years before she could return."

Whatever insights Rana may have into the mind and behaviour of her erstwhile companion, and what he said to her on that June night, she is not telling, and may never tell. Nepal has yet again shown itself to be a country synonymous with beauty, cruelty, and mystery.

Blood Against the Snows: the Tragic Story of Nepal's Royal Dynasty, by Jonathan Gregson, is published by Fourth Estate at £16.99 in UK