Shifting allegiances ... Sihanouk attends a ceremony to transfer relics of the Buddha in Phnom Penh in 2002.

Shifting allegiances ... Sihanouk attends a ceremony to transfer relics of the Buddha in Phnom Penh in 2002. Photo: AFP

Norodom Sihanouk, the former king of Cambodia who survived half a century of political manoeuvring in which his country was sucked into the Vietnam War and endured the murderous regime of Pol Pot, has died. He was 89.

The monarch, who abdicated in 1955 and again 49 years later, died of natural causes in Beijing where he was undergoing medical treatment, Associate Press reported. Sihanouk, who maintained houses in the Chinese capital and Pyongyang, North Korea, suffered from diabetes and prostate cancer.

His principles were self-preservation and terrific patriotism 

Prince Sisowath Thomico, a royal family member who was also Sihanouk’s assistant, said the former king suffered a heart attack at a Beijing hospital.‘‘His death was a great loss to Cambodia,’’ Thomico said, adding that Sihanouk had dedicated his life ‘‘for the sake of his entire nation, country and for the Cambodian people’’.

Turbulent decades ... Sihanouk meets the Australian prime minister Gough Whitlam in Beijing as the Vietnam War neared its end in November 1973.

Turbulent decades ... Sihanouk meets the Australian prime minister Gough Whitlam in Beijing as the Vietnam War neared its end in November 1973.

Notorious for switching allegiances, Sihanouk oversaw independence from France, broke off relations with the US during the Vietnam War and weathered two periods of involvement with Pol Pot's Khmer Rouge, the regime blamed for the deaths of about one in five of the country's people.

"He has a mixed legacy," said David Chandler, a US diplomat stationed in Cambodia in the 1950s, who lectures at Monash University. "His principles were self-preservation and terrific patriotism. He made people feel that they were worthwhile and their country was worthwhile."

Sihanouk held numerous posts, including prime minister, president, and leader of various governments-in-exile before returning to Phnom Penh in 1991 and being appointed constitutional monarch in 1993. He was succeeded in 2004 by his son, King Norodom Sihamoni.

Changing roles ... Sihanouk in 1941.

Changing roles ... Sihanouk in 1941. Photo: AP

Norodom Sihanouk was born in Phnom Penh on October 31, 1922, and educated at the French Lycee in what was then Saigon, Vietnam, before continuing his studies in France. He was chosen at the age of 18 by the French colonial administration to succeed his grandfather as king.

The young monarch turned against his colonial backers, campaigning for and winning full independence in November 1953. He abdicated in 1955 in favour of his father so that he could enter politics. As Prince Sihanouk, he set up the Sangkum Reastr Niyum – the People's Socialist Community party.

"At that point he basically ended royalty in Cambodia," Professor Chandler said. "He just didn't want to be king; he wanted to be the boss."

Dubious allies ... Sihanouk with the Khmer Rouge leader Khieu Samphan in the early 1970s.

Dubious allies ... Sihanouk with the Khmer Rouge leader Khieu Samphan in the early 1970s.

Caught up in the competing interests of the Soviet Union, the US and China, Sihanouk attempted to steer a neutral path in foreign policy, becoming a founding member of the Non-Aligned Movement. In 1965, he broke with the US over the Vietnam War, allowing the North Vietnamese to set up bases in Cambodia.

Ousted in a US-backed coup by his prime minister Lon Nol in 1970, Sihanouk sided with a band of communist resistance fighters known as the Khmer Rouge. When the group swept to power five years later, he was appointed nominal head of state.

He resigned in 1976 and was placed under house arrest as the Khmer Rouge embarked on a radical transformation of Cambodian society. Pol Pot's government forced the evacuation of the capital and other urban areas and embarked on a killing spree to eradicate intellectuals and ideological opponents.

Estimates of the death toll vary, with Amnesty International putting the number at 1.4 million out of an estimated population of 7.1 million.

Sihanouk, with other Cambodian factions, again forged a coalition with the Khmer Rouge after Pol Pot was forced from power by the Vietnamese in January 1979. The group was created to oppose the Vietnam-backed government of Heng Samrin; a decade of civil war followed.

"The humble people of Cambodia are the most wonderful in the world," Sihanouk said in 1979, according to the 1980 book Sideshow by the British journalist William Shawcross. "Their great misfortune is that they always have terrible leaders who make them suffer. I am not sure that I was much better myself, but perhaps I was the least bad."

Sihanouk's path back to power began in August 1989 when Cambodia's factions met under United Nations auspices in Paris. Agreement was reached on a comprehensive settlement the following year, and in 1991 Sihanouk returned to Phnom Penh to begin the reconstruction process ahead of nationwide elections in May 1993.

He largely thumbed his nose at the UN Transitional Authority in Cambodia, which had executive powers in the run-up to the election, wrote the journalist Henry Kamm in his book Cambodia: Report From a Stricken Land.

"Where was Sihanouk, the hope of the international community for persuading Cambodians to make peace and establish badly needed national solidarity?" Kamm wrote. "He ostentatiously neglected his chairmanship of the Supreme National Council, hardly honoured his country with his presence and sent a stream of sarcastic or petulant fax messages to Phnom Penh from abroad to give vent to his disdain for Untac."

Aside from politics, Sihanouk was a keen musician and produced and directed about 20 films – all about Cambodia. He routinely invited diplomats for lengthy karaoke sessions and maintained a blog.

"I never thought of film-making as a simple amusement or artistic activity," he wrote in 1995. "I wanted, and still want, to show my country, its past and contemporary history, its culture, its people, and express my feelings regarding certain facets of our nation's life. The star of my films is never an actor. It is always Cambodia."

Bloomberg, AP