Kim Jong-Il: Leader of North Korea who deepened the cult of personality in his country following the death of his father

Supreme Leader: Kim inspects his troops in Pyongyang (Rex)

It is one measure of the cult of secrecy surrounding North Korea's leader Kim Jong-Il that his demise was rumoured long before he actually died yesterday. One professor at Tokyo's prestigious Waseda University argued in a best-selling book that the "Dear Leader" had succumbed to diabetes in 2003 and had been replaced by several doubles. "Common sense cannot take the measure of North Korea's uniqueness," wrote Toshimitsu Shigemura in The True Character of Kim Jong-il.

Biographers attempting to chronicle the life of the North's leader inevitably hack through dense thickets of innuendo, disinformation and ornate propaganda. What is known for sure is that Kim emerged from behind the giant shadow of his father, Kim Il-Sung, on 8 July 2004, when Radio Pyongyang famously announced that the "Great Heart" had stopped beating. In reality, power had begun passing from the nation's legendary founder to his eldest son much earlier.

On the other side of the bamboo curtain, many wondered if Kim Il-Sung's death would bring reforms of the kind that revolutionised China after the death of Mao Zedong in 1976. Kim Junior had a reputation as a forward thinker who had once ordered bureaucrats to toil among ordinary workers to force them closer to the people. His support for foreign investment, love of popular culture and even his then fashionable bouffant hairdo were taken as signs that he was a break with the past.

Instead, as if to show that the isolated country would continue to fossilise, Kim deepened the cult of personality surrounding his father by arranging for displays of mass weeping after he died. More huge statues and elaborate portraits were commissioned and official mourning continued for another three years. The Great Leader was declared president in perpetuity and his policy of juche, or self-reliance, extended, ensuring economic stagnation. Official histories of his fight with the Japanese Imperial Army in the Second World War even had him walking on water.

Only a miracle would have ensured that the eldest son of this God-like figure emerged unscathed from his childhood, even if it had not been marred by tragedy and isolation. Kim's birth in 1941, during his family's exile in Russia in the war against Japan, was followed by the death of his brother, who drowned in the family's Pyongyang garden in 1948, and his mother, Kim Il-Song's first wife Kim Jong-suk, in childbirth a year later. Little maternal love came from the country's new first lady, his father's ex-mistress. It is not difficult to imagine how the young boy, indulged by a succession of anonymous handlers desperate to win favour from his distant father, could have become the capricious, wilful and sometimes cruel adult of repute.

Kim's early life was soon window- dressed by the state's diligent chroniclers. In North Korean biographies, his birth was marked by a double rainbow and a new star. Unlikely stories about his mental and physical prowess punctuated his life: One had him hitting 11 holes-in-one in his first round of golf and finishing 38 under par. Movies extolling his great mental and physical prowess record that he came down from the heavens accompanied by a huge snowstorm. "When he shouts, huge storms happen," said one.

Throughout his childhood, Kim's father was consumed with the problems of the fledgling nation, first as it emerged, bloodied and scarred from colonisation under Japan in 1945, then by the 1950-53 war with the South that divided the Korean Peninsula. The Cold War that followed, squeezing Pyongyang between the US-backed Seoul dictatorship and communist China, and laced with the constant threat of nuclear annihilation, profoundly shaped the country's collective psyche, turning it into what long-time Pyongyang watcher Gavan McCormack calls the "Porcupine State": prickly, bellicose and isolated. Permanent, if suspended, war with the South only added to the sense of siege and paranoia.

How deeply this affected Kim can only be guessed at. Did he watch with unease as the outside world transformed, leaving his country frozen in amber? The few who have met him describe a self-aware, even intelligent man who jokes about his hermit status. Both Japanese leaders, Junichiro Koizumi and Shinzo Abe described him as "rational" and "logical." But the nepotistic transfer of power from father to son may have encouraged him to pander to the more conservative elements of the state's ruling apparatus.

He almost certainly faced resistance: Pyongyang-watchers note that Kim was only officially elected leader of North Korea in September 1998, four years after his father's death, suggesting that a man until then widely viewed as a weak, vain playboy had failed to consolidate power. But he had clearly also begun running key organs of the state by the 1970s and was probably in control of the ruling Korean Workers' Party by the early 1980s. Although not officially named supreme commander of the armed forces – the bedrock of power in the North – until 1991, Kim was already effectively in charge of the country by 1985, according to journalist Bradley K Martin's acclaimed book Under the Loving Care of the Fatherly Leader.

Kim came to office during the country's worst crisis in its half-century existence. Until the 1970s, the North rapidly industrialised and boasted growth rates equal to if not better than its southern rival, even attracting thousands of immigrants. But as he began taking the reins from his father, the centrally planned economy was showing familiar signs of stagnation, a process that accelerated following the 1991 collapse of the Soviet Union, Pyongyang's main sponsor. By the mid-1990s, widespread reports of famine, compounded by a series of natural disasters, were coming from reliable sources, with claims of 2-3 million deaths. The new leader was faced with a profound choice: engage with the outside world or remain frozen in time.

What happened next is one of the most controversial and vexing issues of post-Cold War geopolitics. Did Kim see the North following China to gradual engagement with the West, or would he sharpen the spines of the Porcupine state? There is evidence for both views. According to the former Pyongyang insider Kim Hyun-Sik, the Dear Leader concluded in the 1990s that his country could box above its weight if it prioritised military power. "Kim has managed to extract resources from wealthier and stronger states by manufacturing crises and generating international instability," he says in The Secret History of Kim Jong Il. "His brand of nuclear blackmail is a virtual guarantor of bottomless international aid for the world's most militarised society."

How much help the North has received may be impossible to calculate. Since the famine stories began leaking out, the US, Japan, South Korea, China, the United Nations and many other countries and private donors have poured food, cash and assistance into the country. The flow of aid is heavily politicised and has been suspended during Pyongyang's frequent spats with its international enemies, but it is substantial: the UN World Fund Program is appealing for $500 million to deal with the North's needs over the next year alone.

There are also strong signs from the period suggesting a proud country keen to normalise ties with Washington, Japan and South Korea, and constantly knocked back. In 1993-94, Kim took the country to the brink of confrontation with the Clinton Whitehouse by producing plutonium for a long-planned nuclear weapon, before agreeing to a freeze in return for construction of light-water nuclear reactors. The so-called "Agreed Framework" collapsed under the presidency of George W Bush, with allegations of bad faith on both sides. Bush and his team, who famously branded the North one-third of the "Axis of Evil," accused it of secretly restarting the weapon's programme; Pyongyang said the US had reneged on its pledge to supply fuel and other aid.

If Kim overplayed his hand during this period, so did the US president. As the North Korea specialist Don Oberdorfer notes, before the "Axis of Evil" speech, Washington "certainly recognised Kim Jong Il," with President Bill Clinton exchanging letters with the North Korean leader. Like many observers, Oberdorfer laments the element of personal insult introduced by Bush, who called Kim a "tyrant." The exchange sent relations into a deep freeze from which they have yet to recover.

Similarly, a bold attempt to build bridges with Japan backfired on Kim in 2002 when he misjudged the hostile reaction to his personal admission that his agents had engaged in a bizarre plot to kidnap Japanese citizens in the 1970s and '80s. Only ties with the South appear to have improved, with regular if friction-filled political contact and the construction (beginning in 2003) of the Kaesong Industrial Region, the first stage in a massive collaborative development between the two old enemies. Occasional joint sporting events also suggest light at the end of the tunnel – when the symbolic ruins of the past can be overcome: a Fifa qualifying match between the two sides scheduled in Pyongyang for March this year was almost scrapped after North Korean officials objected to the playing of the South's national anthem. The game eventually took place in Shanghai.

Still, the country Kim left behind is deeply troubled: in McCormack's words, "beyond the 'pale' of civilisation, closed, threatening, idolatrous; yet, at the same time... also, on the surface at least, an urban, educated society, a 'modern industrial state.'" Possibly nuclear-armed, with the fourth biggest standing army in the world, obsessed with old enemies; the North has still to absorb the profound changes that have taken place since the 1980s, particularly the remarkable transformation of the South. Perhaps the best that can be said for the man who guided the county through this period is, in the words of Columbia Professor Charles K Armstrong: "Kim Jong-Il might be bad but it could have been worse."

Kim Jong-Il, politician: born (officially) Baekdu Mountain, Korea 16 February 1942, (unofficially) Vyatskoye, Russia 16 February 1941; Supreme Leader of the Democratic People's Republic of Korea (North Korea), General Secretary, Workers' Party of Korea, Chairman, National Defence Commission of North Korea, Supreme Commander, Korean People's Army; married four times, confirmed children: three sons and one daughter; died North Korea 17 December 2011.