Japan has one of the most unique religious landscapes in the world. A host of animistic folk traditions, gathered under the umbrella of the native Shintō religion, coexists alongside various strands of Buddhism imported and adjusted to local sensibilities. But as any scholar of Christianity in Japan will tell you, the history of religion here has had some dark times.
Perhaps the worst of all was the period of religion-fueled mania which swept the country in the era leading up to World War 2. During this time, the fanatical idea that the Japanese emperor was a literal manifestation of divinity took such a tight hold on the country that millions were willing to lay down their lives in his service. In a country now regarded as a paragon of dignity and restraint on the world stage, how could this have happened?
The roots of the answer stretch back all the way through Japanese history, from its mythical beginnings right through to the hyper-nationalism of the modern era. The idea of divine nobility is longstanding in Japan, used to legitimize and naturalize the political order for centuries, not unlike the holy mandate claimed by European kings and queens.

The Age of the Gods and the Yamato Dynasty
The story supposedly begins over 2680 years ago, in the so-called Age of the Gods. This is the mythical era in Japanese folklore, during which the old kami (gods) created and ruled the world before supposedly passing it over to the first emperor of Japan in 660 BC. The Kojiki, an 8th-century document concerning the lives and times of the gods, is the oldest authority on the matter. It’s the closest thing Japan has to a Book of Genesis, detailing how the home islands were created by an original god and goddess, who populated the heavens and earth with their children.
The most significant among them is the sun goddess, Amaterasu. She is the deity worshipped at Ise Grand Shrine — one of the most significant religious sites in the country — and the patron goddess of the Japanese royal family. In fact, throughout history she was said to be more than just their patron and protector; she was thought to be their quite literal ancestor.

The purpose of the Kojiki wasn’t simply to gather together myths and legends for posterity. Rather, it was a way for the ruling Yamato Dynasty to legitimize their power. This was done by claiming direct lineage to the sun goddess herself, by way of a series of dubious mythological emperors along the way. In reality, the first non-fictional emperor of that bloodline took power in 539 AD, according to modern historical study.
Standardized religious mythology was a powerful tool to establish stability and respect towards the rule of the Yamato clan, while also attributing divine heritage to the various other clans and families beneath them. This established a clear hierarchy and imaginary familial ties, superimposed upon the heavens while massaging the egos of these proud families who might otherwise have gotten ideas above their station. Amazingly, the authority which it established has largely held to this day. The family lineage established in 539 AD has run practically unbroken, through 97 different monarchs all the way to the current Emperor Naruhito.
Clearly, this narrative was a powerful one, capable of standing the test of time, but its terrifying potential wasn't fully realized until over a thousand years after the Kojiki was published. But first, the position of the emperor would have to withstand some difficult historical trials.

The Days of the Shōgun and the Meiji Restoration
In the latter half of the 12th century, the Minamoto clan won a war against the Taira clan for influence in the imperial court. By the time the dust had settled, the Minamoto had enough power and influence to effectively take over governance of the country, decentralizing political power across Japan and establishing the Kamakura Shogunate. This was the start of the years of the feudal system, with regular warring among the military clans of Japan to claim the title of Shogun. The emperor remained as the civil head of Japanese society, effectively second in terms of actual power.
So things remained for centuries, bar a few rebellions and reshuffles, with the true seat of power passed among the military clans while the emperor remained the symbolic head of the nation. It's important to note that at this time the emperor was believed to have divine lineage, but he was not worshipped directly. When the Dutch came to Japan in the sixteenth century, they likened the emperor’s situation to the station of the Pope, with the various regional daimyo like the feudal kings of Europe.
This situation only came to an end in 1868. On the 4th of January in that year, the Meiji Restoration was officially declared by the emperor and his supporters, who wished to see Japan leave feudalism behind and enter modernity. Shogun Tokugawa Yoshinobu promptly resigned, but less than three weeks after this event, he and his supporters marched on Kyoto, and were consummately defeated at the Battle of Toba–Fushimi.
Thus the Empire of Japan was formed, with the emperor resuming his position as the political, civil, and military head of the country after a 683-year interim. The nationalism which precipitated and surrounded this event was a breeding ground for all sorts of hardline rightwing views, leading to the militarism which came to define the following decades.

State Shintō
This national fanaticism didn’t come about organically. In fact, it took a concerted effort by the Japanese government to rally the nation to their cause. The Meiji government believed it needed a way to unify national identity to fortify Japan against external influence and compete on the world stage. The myths inherited from the time of Emperor Naruhito gave them a ready-made template with which to do so.
The idea of the emperor having divine heritage had remained in Japanese culture since the publishing of the Kojiki, and it was exploited to no end in the Meiji era. The idea of the arahitogami, or ‘living god’, was pushed through a state-sponsored propaganda campaign that used the widespread Shintō beliefs of the nation as its stock.
This was backed up by the creation of a bureaucratic and authoritarian ‘State Shinto’, a term coined by American analysts to differentiate this state-sponsored endeavor from the everyday traditions it co-opted. Just as the Kojiki had tied together with a series of loosely collected folk practices into one coherent narrative to legitimize the rule of the Yamata Dynasty, the Meiji government likewise attempted to standardize Shintō practice to fortify the status of its latest figurehead, and thereby cement authoritarian rule.

From 1869 onwards, government organizations were established to manage the religion, most notably the Bureau of Shrines in 1900. Over the following decades, they clamped down on Shintō practice which fell outside of state control, standardizing the training of priests and reducing the number of active shrines to effectively nullify the religion and its priests as an independent political force.
In the 1920s, priests who continued traditional shrine practices were increasingly arrested and prosecuted by the Shūkyō Seido Chōsakai, an organization set up to investigate the unsanctioned parts of Shintō which had gone underground, and coerced shrines into pushing the divinity of the emperor as the core tenet of Shintō belief and practice (something previously unheard of throughout the history of the religion). Schools and newspapers were filled with propaganda-laced teachings, stating that the imperial-worshipping practices were a natural and inherent part of the identity of each and every person in the country.
It was by these methods that the religion of Japan was transformed into one of the most powerful propaganda machines the world has ever seen. The imperial cult became absolutely central to the national culture, and the government distributed images of the emperor for citizens to worship in their homes. Entire generations were born under the influence of this newfound religious nationalism, worshipped its imperial figurehead, and ultimately gave their lives for him.

In 1873, the military draft was introduced, and a document known as the Imperial Rescript to Soldiers and Sailors was published 9 years later. This document outlined the moral responsibilities of troops to the emperor, and they were forced to memorize it by heart. The publishing and presentation of the document were accompanied by an imperial ceremony, presented as an edict from the emperor himself, thus solidifying the link between the emperor and the military — now not a secular, civil force but one directly under his divine command.
The culture of militarism led to a campaign of aggression around the region designed to bring Japan up to pace with the established colonial world powers. Taiwan, Korea, and China were three of the greatest victims of this expansionist policy. As the empire gained more ground, it acquired increasing confidence which would lead to Japan’s dramatic entry into World War 2 with the attack on Pearl Harbor on December 7th, 1941.

World War 2 and the Humanity Declaration
Over the years following that event, the world was exposed to just how fanatical and militaristic the nation of Japan had become. In service to the purportedly divine emperor, Japanese soldiers were willing to go to extreme lengths which terrified their enemies in the Pacific Theatre.
The most famous example was the kamikaze bombers: a group of Japanese fighter pilots specially trained in suicide attacks — flying their aircraft directly into American ships. The name literally translates to “god’s wind” — a term first used to describe the typhoons which saved Japan from Mongol invasion in the 13th century.
This proves the religious, nationalistic fervor behind these attacks, and the idea that Japan and the Japanese were specially protected by the divine might of the Shintō gods and their earthly avatar — the Emperor. But the reality was far less noble. In fact, as America began to bear down on the Japanese mainland by taking the Okinawan islands, the Emperor actively encouraged his soldiers to fight until the very end, even going as far as to promote suicidal tactics in the hope of bringing America to the negotiating table.
Soldiers would charge American troops in a suicidal fury, shouting the word banzai — a traditional greeting wishing long life to the Emperor. The inhumane tragedy of this strategy didn’t only affect the conscripted. Even civilians were encouraged or forced by the military, to commit suicide rather than be captured by Allied forces.

After the equally atrocious atomic bombings of Hiroshima and Nagasaki brought an end to the Japanese government’s no-surrender policy, the American authorities who moved in to manage the post-war period were faced with a culture so irrationally gripped in the delusions of the imperial cult they had to first dismantle this ideology before they could hope to move forward.
The solution was the Humanity Declaration. This was an announcement issued by the Meiji emperor Hirohito on the first of January 1946, in which he denied any and all claim to divinity, asserted his status as a human being and debunked the idea that the Japanese held a holy mandate to rule the world. This paved the way for the foundation of modern Japan, with a new constitution that reduced the emperor to a purely symbolic role, and passed the true power over to a democratic parliament.

The Aftermath and the Present Day
Understandably, those who were born and raised entirely under the cloud of State Shintō felt lost after the declaration. The whole world that they had known suddenly evaporated overnight and many struggled to cope with the disillusionment. If you're looking forward to hearing what comeuppance Hirohito received for his part in pushing this narrative, you're out of luck.
With America in need of a Pacific base to monitor the emerging communist powers of the East, they allowed the Japanese emperor to keep his throne in exchange for his compliance. He ruled all the way until 1989, while the head of his military General Tojo found himself taking the flak in the international courts.
Hirohito continued as the symbolic head of Shintō, as does his present-day replacement. However, since the war, all of the rites and rituals he performs are hidden behind the closed doors of the palace — funded by the imperial family themselves according to the terms of the constitution requiring separation of religion and state. Indeed, modern Japan is very careful to keep the two strictly separate, and to celebrate Shintō for the rich and social folk tradition that it always was, rather than the propaganda tool it became.

However, there are still fragments of the Shintō nationalism of old in contemporary Japanese society. Several far-right fringe groups seek to revive the old sentiments on which the power of imperial Japan rested, including veneration of the emperor as the heart of Japanese identity. Though the royal family is careful not to embolden or endorse these groups in any way, their influence is considerable, with an estimated 100,000 active members among the various groups (known as uyoku dantai).
On February 11th, Japan’s National Foundation Day (said to be the day the first mythical emperor of Japan took power), you’ll find these assorted tribes of idiots (there's no sense calling them anything nicer) driving around in cars with mounted loudspeakers to broadcast their propaganda speeches and songs. Ultranationalist groups continue to draw upon centuries-old mythology to justify their modern-day myths of national and racial purity, anti-China sentiment, and Japanese exceptionalism.
Conclusion
Above all, the story of Japan’s emperor worship is about the incredible power of myths. They can be a colorful part of the culture, or manipulated into propaganda to control an entire nation. By co-opting and weaponizing the identity of the Japanese people, the Meiji government was able to use the belief in imperial divinity to aid in pursuing a devastating campaign of warfare and oppression.
The 20th century is full of such warnings — from the fascism of Germany and Italy to the dictator-worshipping communism of China and the Soviet Union. Each is a stark reminder of how collective fanaticism towards an ideology can bring about a state of propaganda-induced mania. However, it's not all a cause for despair. The vast majority of modern Japanese people look back on that period and see it for what it really was, happily condemning its narratives to history along with the Naziism with which it allied itself.