Fifty years ago, on 25 November 1970, Japan’s best-known celebrity, the writer Yukio Mishima, grabbed headlines around the world by the very public yet very traditional manner of his death.

Mishima committed seppuku (Hara-Kiri), the time-honoured way of death of Japan’s warrior caste, the Samurai, from whom he was himself a direct blood descendant. He knelt half naked on the office floor of General Mashita, commander of the toothless Japanese army, the Self Defence Forces (SDF), whom he had just taken prisoner, plunged a short sword, the wakizashi, into the left side of his belly and drew it across his abdomen, disembowelling himself.

At this point, Mishima’s closest lieutenant (and possible lover) 25-year-old Masakatsu Morita, should have delivered the coup de grace to his master by decapitating him with Mishima’s own full-length samurai sword, the katana. But Morita botched the job, failing to hack off the author’s head despite three attempts. Another of Mishima’s young disciples, Hiroyasu Koga, stepped into the breach, striking off both Mishima’s head and then that of Morita. It was a messy end to a ritual that should, according to Samurai lore, have been conducted as carefully and cleanly as a tea ceremony.

Japan’s feudalism and reactionary hierarchy were not easily shaken off

Moments before his bizarre and gruesome end, Mishima had been standing on the balcony of the SDF’s Tokyo HQ, haranguing a bemused audience of some 1,000 young army officers and cadets. Hands on hips, clad in the camp, tight fitting, and rather Ruritanian uniform he had designed for his own private army, the Totenokai (“Shield Society”), his voice almost drowned out by a helicopter clattering overhead, Mishima called on the SDF to become a real army, repudiate treaties with the US that had reduced Japan to a vassal state, and restore Emperor Hirohito to the divine status that the US had forced him to disavow in 1946.

The reaction of the audience was what he had expected: a derisive chorus of hoots, catcalls and mocking laughter. With a final defiant triple cry of “Banzai! Long live the Emperor!” Mishima and Morita retreated back into Mashita’s office to meet their self-induced fate.

If it is utterly impossible to imagine a similar scene in Britain – a notable novelist of the day (Kingsley Amis say) raising a comic opera militia as bodyguards for the Queen, training it with the Household Cavalry, visiting and trussing up the chief of the defence staff at Sandhurst, demanding he mount a coup to restore Her Majesty’s divine right to rule, and then ritually disembowelling himself – then that is a measure of how very different the islands of Nippon were and are from our own dear islands or indeed from any other nation on Earth.

Japan’s exceptionalism was partially born from its geographical position, and partly came from a deliberate policy of self-isolation called Sakoku (“closed country”) during the rule of the Tokugawa shogunate; a clan military dictatorship that effectively ran the country for two and a half centuries from 1600 until the arrival of the US Navy’s “Black Ships” commanded by Matthew Perry in 1853.

The military became increasingly worried that Japan’s traditional values were being sapped by western materialism

In a muscular example of gunboat diplomacy, Perry compelled Japan under threat of force to drop its Sakoku regime and begin trading with the outside world. There had already been some severely limited contact with the rest of the planet. Dutch traders from the East Indies had been permitted to open an enclave around the port of Nagasaki, but fearful of “contamination” from Christian missionaries, all such contacts were strictly controlled. Unlucky foreign sailors shipwrecked on Japan’s coast were executed, and the occasional Japanese envoy sent to learn and copy trade and technology secrets abroad risked suffering the same fate when they returned home.

But after Perry’s visit, all this changed. During the so-called “Meiji era”, named after the inbred Emperor who occupied the Chrysanthemum throne between 1867-1912, Japan was rapidly transformed from a feudal state largely populated by peasants into a modern western style industrial, military and financial superpower. It conquered Korea, fought successful wars with China and Russia, smashing the Russian fleet at Tsushima in 1905, and earned its place among the Allies that won World War One.

But feudalism and its reactionary hierarchy were not easily shaken off. Although Japan had introduced a parliamentary system as part of its modernisation, real power remained in the hands of a military caste heavily imbued with the aggressive and austere Spartan ethos of the Samurai.

Increasingly worried that Japan’s traditional values were being sapped by western materialism and its workers infected by the virus of Marxism, during the 1920s and 1930s the military – influenced and infiltrated by nationalist secret societies with picturesque names like “Cherry Blossom” or “The League of Blood” – increasingly flexed their considerable muscles.

Inspired by the rise of fascism in Europe, their aim was to carve out an empire in Asia and purge the state of the corruption of democracy. Beyond the control of weak parliamentary governments, the military proclaimed the puppet state of Manchukuo in China’s Manchuria in 1931, nominally headed by China’s last Emperor, Pu Yi. The following year, in an attempted coup, they assassinated the veteran prime minister, Inukai Tsuyoshi, who had been trying to rein in their power.

Another intended victim of one military coup was to have been Charlie Chaplin

Oddly, another intended victim of their coup was to have been Charlie Chaplin. The British-born Hollywood star was then at the height of his fame and on his first visit to Japan. Chaplin saved his life by electing to watch a sumo wrestling match with Tsuyoshi’s son rather than attend the reception where he would have been killed. The killers’ motives were mixed: Chaplin represented the vulgar commercial culture they believed was corrupting the country, and they also thought his death might trigger the war with the US that they saw as inevitable.

In a sign of their increasing power, the nationalist naval officers who had shot Tsuyoshi were let off with light sentences. Thus emboldened, the fanatical young military caste struck again in February 1936 with a second coup. Marching through a snowbound Tokyo, they succeeded in killing several cabinet ministers and officials of the imperial household, but failed to take the Emperor’s palace, and senior officers suppressed the putsch.

The young Emperor Hirohito, who had come to the throne in 1927, angered by the murders of his staff, insisted on the execution of the leading plotters, but from now on state power was firmly in the hands of the military caste who were bent on war. Mishima, a sickly ten-year-old child at the time, would fetishize the “February incident”, as the coup was euphemistically called, in a 1960 story titled Patriotism which in 1966 he made into a film directed by and starring himself.

In the black and white film, owing much to traditional Noh and Kabuki theatre, he plays a young lieutenant who, following the failure of the coup, is ordered to execute the plot’s leaders.

It was in the atmosphere of the Pacific War and its supreme crisis that Yukio Mishima came of age

Caught between his sympathy for his comrades and his inability to disobey an imperial command, he decides to commit seppuku together with his beautiful young bride. The camera contrasts snow and blood and lingers lovingly over the entwined couple as they copulate. Later, just as caressingly, it shows their naked bodies in death. The film not only eerily presages Mishima’s own dramatic death four years later, but starkly underlines one of his major themes: the marriage of love and death. Eroticism can only achieve its final and highest climax when it is coupled with extinction.

Japan’s military rulers began a full-scale war against China in 1937, accompanied by savage atrocities like the “rape of Nanking”. Then, after allying with Nazi Germany, they launched their surprise assault against Pearl Harbour in December 1941. At the same time, with embarrassing ease, they demolished Britain’s Empire in east Asia with the lightning conquest of Hong Kong, Malaya, Singapore and Burma.

After the tide of the Pacific War turned against Japan, the strong element of extremism in the national character came to the fore as, fighting fanatically, its forces were pressed back, island by island. It was in this atmosphere of supreme crisis that Yukio Mishima came of age.

It does not take a psychoanalyst to trace Mishima’s obsessions and compulsions to his childhood

He had been born in 1925 as Kimitake Hiraoka. (Yukio Mishima was the pen name chosen at random by the editors of the magazine that published his first story.) The son of an upper-class family who had been in government service for generations, his childhood was weird even by contemporary Japanese standards. Hardly out of the cradle, he was snatched up by his paternal grandmother Natsuko, a forceful matriarch descended from the shoguns, and spent his first decade as a captive in her sickroom, forbidden to meet or play outside with other boys. His only occasional companions were female cousins and their dolls.

It does not take a psychoanalyst to trace Mishima’s obsessions and compulsions – his preoccupation with death, decay, gender confusion and ancient traditions – to this background.

The boy retreated into reading, devouring the books in Natsuko’s library which gave him a precocious education in world literature and history – he taught himself German – as well as traditional Japanese poetry. His family took diametrically opposite attitudes to his early interests. When he began to write stories at the age of 12, his father ripped up his manuscripts and ranted against such effeminacy. By contrast, his mother encouraged his early literary efforts, and Natsuko took him to performances of traditional Noh and Kabuki theatre, which became an adolescent passion that lasted a lifetime.

Mishima revealed an iron will in resisting his father’s attempts to force him into becoming a state bureaucrat like himself. He ran his school’s literary society and was bullied by more hearty schoolmates. Determined to be a writer, he published his first story in 1941, aged 16. Bowled over by the young talent, the magazine’s editorial board gave him his pseudonym to shield him from his father’s wrath.

In 1944, Mishima received his military call up. A puny youth – he stood little over 5’1, tiny even by Japanese standards – he faked tuberculosis symptoms at his medical examination to avoid the draft. This episode left him with a lifelong sense of shame, which he compensated for with the militarism and body building of his last years. In 1945, the war’s final year, Mishima idolised the kamikaze (“Divine Wind”) suicide pilots who flew their planes into US warships, and spoke of his desire to join them, writing in his diary of the necessity of preserving the spirit of “Japanese irrationality” in world culture.

Mishima’s motive was to reach physical perfection before age and decay set in

The immediate post-war years saw Mishima make his breakthrough into national and international literary stardom. His first major novel Confessions of a Mask (1947), which dealt with a homosexual who had to hide his sexual identity, was a huge hit. Mishima’s own orientation was complex. He had heterosexual romances, and even met the future Empress Michiko with a view to marriage. In 1958, he wed Yasushi Sugiyama, an artist’s daughter, and the couple had two children.

However, his oeuvre is saturated with homoeroticism, he frequented gay bars (allegedly while researching a novel), and his final decade was spent mostly in male company. 1958 was a turning point. Not only did Mishima marry, but in his late twenties, again demonstrating his remarkable will, he took up martial arts, weight training, and body building in a startlingly successful effort to transform his feeble frame into that of a Japanese Arnold Schwarzenegger.

He had the results taken by a fashion photographer in a series of narcissistic shots variously showing off his near naked body posing on a motorcycle, brandishing a Samurai sword, trussed in rope bondage, and finally transfixed with arrows as the martyred St Sebastian. Again, one is tempted to make a comparison with Britain: it was akin to if the diminutive Martin Amis had taken to haunting gyms before having the results snapped by David Bailey for a glossy Vogue centrefold spread.

Though the sadomasochistic exhibitionism was clearly rooted in Mishima’s own psychology, he made an aesthetic defence of it. His motive, he claimed in interviews, was to reach physical perfection before age and decay set in.

By the 1960s, Mishima’s best-selling novels, with their ambivalent sexuality, luxurious style, and romantic themes, had made him an international celebrity. His attitude to the West was contradictory: he gave TV interviews in fluent English, travelled in Europe, visited the States and even enjoyed Disneyland. At the same time, he defended Japan’s sovereignty, derided its slavish dependence on the American alliance, and deplored the prosperous new Japan of transistors, cars and corporate conformity that was emerging after the shame of wartime defeat.

At the beginning of the turbulent Sixties, politics began to preoccupy Mishima. Deeply impressed by the assassination of socialist leader Inejiro Asanuma by a right-wing youth wielding a wakizashi sword on live TV, and by the assassin’s subsequent suicide, he followed the violent student demonstrations against the renewal of a Security Treaty with the US with admiration – even though most of the students were Leftists.

His suicide was as much an artistic and spiritual final bow as it was a political protest

In 1968, after himself training with the SDF, he formed his own private army, the Totenakai, with an 80-strong membership of right-wing hero-worshipping young men. Its ostensible purpose was to defend the Emperor, though Mishima made clear that he meant the Imperial institution rather than the actual person of the reigning Emperor Hirohito – whom he regarded as a liberal feebleton who had forfeited respect by abandoning his divinity under American pressure. It is a measure of Mishima’s status that he was on good terms with the ruling political class who allowed him to train the Totenakai alongside the regular SDF.

On 25 November 1970, having left the final pages of his masterpiece “The Sea of Fertility” on his desk with instructions to deliver the novel to his publisher, Mishima drove with four members of the Totenakai to the SDF HQ. A familiar figure there, he was admitted without question – despite the fact that he was clutching a Kanata sword. Once in General Masata’s office, after a few minutes of polite chit chat and a cup of tea, the visitors seized the startled General, gagged him and tied him to his chair. They then barricaded the office and Mishima stepped on to the balcony for his final performance.

Though the world’s media reported Mishima’s last act as an attempted but bungled coup, it was actually rooted in his personal psychology and aesthetic as much as his politics. The act had been carefully planned as the inevitable climax of his life. He had not expected it to succeed and would probably not have known what to do if the SDF had fallen in behind him and marched on the Imperial Palace as their forebears had done in the 1930s. The action was as much an artistic and spiritual final bow as it was a political protest.

At 45, Mishima knew that his bodily perfection was on the wane; he had seen the coveted Nobel Prize for Literature go to his mentor Yasunari Kawabata rather than him, and realised that it would be unlikely to go to another Japanese writer anytime soon. He was increasingly out of sympathy with the path of crass commercial conformity his beloved country was taking; and his strident politics looked like an archaic relic from another age. It was time to go, and, as the showman he was, he made his exit as public and lurid as possible.