RAIJŪ 雷獣
Pronunciation: RYE-joo
Translation: Thunder Beast or Thunder Animal
Overview
The raijū is a yōkai related to thunder, lightning, and storms—in fact, some legends state that it is entirely composed of lightning. It’s smaller, more frenetic, and much more difficult to identify than the similar and better-known thunder and storm god, Raijin (see the Raijin and Fūjin entry). It’s been reported to live above the clouds or deep in the mountains. Wherever it resides, this mysterious and volatile brute unleashed a considerable amount of mayhem during the Edo era (1603–1867), and stories abound to chronicle it.
Descriptions about what the raijū actually looks like are numerous and diverse. It seems to have appeared in various animal guises—oftentimes bizarre ones at that.
You’ll frequently see it as a blue and white wolf enveloped in a web of lightning. But there are also tales of it looking like a puppy, tanuki (Japanese racoon dog), cat, weasel, squirrel, seahorse, crab, or tangled ball of lightning, just to name a few. When it appears in an animal shape, it typically has long inward-curving claws, webbed fingers, and fangs.
Some descriptions come from written works, such as the prolific author Kyokutei Bakin’s book Gendō Hōgen (玄同放言). There the raijū resembles a wolf with two front legs, four hind legs, and a split tail (like a nekomata—see the Bakeneko and Nekomata entry). Sunkoku Magazine (駿国雑誌), which was published in the mid-1800s, reported there was a raijū living on Takakusayama (高草山) in present-day Fujieda City, Shizuoka Prefecture, that was about 24 inches (60 centimeters) long and resembled a weasel or a cat. It had long reddish-black fur with black dots, round eyes, small round ears like those of a mouse, a very long tail, and claws. During thunderstorms, this raijū could be seen riding on clouds and accidentally crashing into trees, breaking them apart, as well as harming anyone who happened to be nearby.
Background and Popular Stories
Raijū are often seen in the company of the thunder and storm god, Raijin. It seems the thunder beasts are sort of pets to Raijin. There is one problem with their friendship, though—how Raijin wakes the raijū up. It’s a mystery how it’s done, but raijū like to nestle and sleep in people’s belly buttons. When Raijin wants to rouse a raijū and call it back to him, he shoots lightning arrows at his little friend. The unfortunate outcome of this method is grave injury to the sleeping human.
Much like the accounts of its appearance, tales of the raijū are also plentiful and varied. Most of the time, raijū are quiet and harmless, but when weather turns foul, they get agitated and start zooming around. They can ride down to Earth on a peal of thunder or streak of lightning or in a ball of fire. Then they start jumping around frantically from tree to tree, around fields, and even between buildings, wreaking havoc as they do. Have you ever seen a tree scarred by a lightning strike? That is actually a vicious scratch from a raijū’s long claws. Then there are tales of them just dropping out of the sky during a storm.
There are also legends of raijū living in the mountains. In Ehon Hyaku Monogatari (絵本百物語), or the Picture Book of a Hundred Stories (1841), in a chapter titled “Thunder,” there’s a story of a raijū that settled in the hills of Tochigi Prefecture. It was usually as docile as a cat, but at the first sign of rain clouds, it would rush into the air and start racing about, full of frenetic energy.
All this racing around destroyed crops and caused a lot of damage. If lightning struck a particular rice field, the townspeople would immediately erect a tall bamboo pole decorated with sacred shimenawa ropes at the spot. This would keep the raijū from descending again and bringing any more devastation. This story is especially interesting because in other places in Japan, a lightning strike to a field was thought to be a lucky event. Superstition said it reenergized the soil and brought abundant harvests. There’s even an old saying: “Kaminari ga ōi to hōsaku ni naru” (雷が多いと豊作になる), which means, “If there is a lot of thunder and lightning, there will be a bountiful harvest.”
In the mountains of Tochigi Prefecture, during the summer months, raijū would pop their heads out of holes and gaze up at the sky. Once they found what they were looking for, in a roll of thunder, they’d leap swiftly into the air and jump on top of their favorite suitable cloud.
Finally, some people say that the chimeric nue defeated by Minamoto no Yorimasa (see the Nue entry) was actually a raijū, given they can appear as so many different creatures.
There are many folktales involving the raijū—this one involves a real person and (mostly) real events. Once, there lived a great samurai named Tachibana Dōsetsu (1513–1585) who was in possession of a famed sword called Chidori (千鳥), or One Thousand Birds. Dōsetsu was out one day when he decided to rest under a tree and cool off from the summer heat. Suddenly, the skies grew dark and foreboding, and a crackle of lightning exploded very close to him. Dōsetsu withdrew Chidori and, with unimaginable speed, sliced through the thunderbolt, saving his own life and leaving dead on the ground a smoldering raijū. He soon renamed his sword from One Thousand Birds to Raikiri (雷切), or Lightning Cutter.
Unfortunately, the incident left Dōsetsu’s left leg paralyzed. As a testament to the man’s bravery and determination, Dōsetsu didn’t let a partially incapacitated body stop him. This legend still went on to fight another thirty-seven battles, charging in on a horse, always with Raikiri by his side.
In Modern Stories
In the anime Inuyasha, the Thunder (Beast) Brothers, Hiten and Manten, are called Raijū Brothers in Japanese. Another interesting sighting is in the manga and anime Naruto. In it, there are techniques called Chidori and Raikiri, referencing Tachibana Dōsetsu’s legendary sword. And in the movie Pacific Rim (2013), one of the giant monster kaijus is called Raiju.
Beyond anime and film, you can find many riffs on the raijū in the Pokémon pantheon. A few are: Raikou, Jolteon, Manectric, Luxray, Zeraora, and let’s not forget Raichu and the king of all Pokémon, Pikachu itself.