When we talk about the 10 reasons why ninja have become the ultimate puzzle of history, we’re really diving into a world of shadowy tactics, whispered legends, and deliberate secrecy. The Japanese shadow‑warriors of the 15th and 16th centuries were masters of stealth, combat, and infiltration—collectively known as ninjutsu—and they guarded their knowledge with a ferocity that still mystifies scholars today.

Understanding the 10 reasons why the ninja stay mysterious

10 People Got It Wrong Then, Too

Ninja were widely employed in the 15th and 16th centuries. A common misconception was that ninja were in direct opposition to samurai. Often, ninja and samurai would fight on the same side of the battlefield. Ninja were everywhere, hired in the household of any lord worth his salt.

As they became more important in national events, the rumors about them grew. They were said to be able to vanish into thin air. They moved as silently as ghosts. They could read an opponent’s mind. Some of the growing rumors were true. Many were not.

There was no time when ninja were accurately understood, outside of the ninja themselves. If anything, ninja were even more mired in superstition than they are now. People believed they possessed supernatural powers, almost akin to superheroes.

For such a large force of people, the lies about them in the 16th century were widely successful. It’s difficult to detail how much information has been lost due to the great superstition they inspired in people around them.

9 Ninja Encouraged The Rumors

Ninja did little to halt the rumors that were raising them to near legendary status. In fact, they encouraged the rumors. The elevated prowess of ninja did not begin in the 20th century, but at the time, the ninja were at their peak.

They used these tales as methods of intimidation and misdirection. Their dark reputation discouraged many enemies and would‑be invaders, making the ninja seem larger‑than‑life. Wildly inaccurate rumors helped them conceal their true practices.

Written documentation didn’t shed conclusive light on the ninja, either. Authors were given to adding ninja powers to biographies to liven up their writing. Tales of ninja exploits were often embellished and portrayed as historically accurate. It makes sifting fact from fiction difficult to this day.

8 They Were Raised In Isolation

This refers to the isolated province of Iga. Ninja were hard to measure in terms of numbers and location, but all agreed that the bulk of the Japanese ninja resided in Iga. It had a nigh perfect defense.

Iga was ringed by mountains, with narrow passageways as the only access. It was defensible by a smaller number of men. It gave ninja a way to live unrecognized before they went into the outside world. No information conclusively points to when Iga became the center of ninjutsu, but it could have been several centuries before the ninja’s downfall.

That downfall came about only with overwhelming force. Oda Nobunaga’s son Oda Nobukatsu ruled the Ise province, but he was enamored with the idea of adding Iga to his domain. He entered Iga, where he began to build a castle for the base of attack.

The ninja burned it down before it was completed. Humiliated, the young Nobukatsu tried to invade with a force 8,000 strong. The ninja used the terrain to ambush him, killing hundreds and possibly thousands with minimal losses to their side. Nobukatsu was forced to retreat and face his father’s wrath for his foolish venture.

When two Iga ninja approached Oda Nobunaga with inside intelligence, he took a force of over 40,000 and invaded Iga. He split his forces into six armies that invaded six passageways at once, crushing the Iga ninja with brute force. Their mass solitude was at an end, but they still carried their teachings.

7 The Art Of Ninjutsu Was Not Greatly Recorded

Ninjutsu teachings were passed down by teachers who demonstrated the ninjutsu rather than wrote it down. It was only during peacetime that some older ninja would write accounts of their ninjutsu. Many more held it in secrecy.

Today, several families claim that they are descendants of ninja who learned from earlier generations by practical teachings, not writing. There has yet to be evidence for this. But it remains a fact that learning ninjutsu through writing was often entirely omitted from the education of future ninja.

Samurai followed a strict code. However, ninja had a philosophy of totality. This belief encompasses the idea that the universe has a balance and people are part of that balance. There is good and bad, warm and cold, and an awareness of this was essential to the ninja.

Such a wider kind of morality called for the ninja to learn from his master formally but also train in what he found most useful. Anything useful could be used regardless of Bushido (“the way of the warrior”). So it freely changed from generation to generation, making it all the more difficult to track.

6 There Were Countless Versions Of Ninjutsu

The teachings differed among the various schools of ninjutsu, which emphasized different aspects of the ninja. There is a story about a governor named Bakkansai Jotei who assaulted a rebel holed up in the castle of Sawayama.

When the mountainous terrain foiled his assaults, he called for a ninja named Dojun to find a way to breach the castle. Dojun responded by gathering 48 men. He infiltrated the castle and set fire to it.

While they burned and killed from the inside, Jotei led an assault from the outside and the castle fell. The 48 ninja split off into 48 schools of ninjutsu, almost all of them centered in Iga.

Countless schools of ninjutsu were located in Iga. Some emphasized the art of combat, while others emphasized the art of stealth. These different schools have made it difficult for even honest ninja biographers to give an authoritative account on ninja.

They are often biased by their ideals and skills and project them onto other schools. Historians have often tried to find the true overarching beliefs among ninja rather than ones specific to a select few.

5 They Were Secretive Toward Each Other

Ninja kept their teachings secret from outsiders. They even hid their teachings from other schools. Secrecy was not considered an insult. It was a way of life for the people who practiced the art of deception, espionage, and infiltration.

They had a system of rank that would support this anonymity. There were three ranks in the household: Genin, Chunin, and Jonin. The Jonin were the masters, relaying orders to the others. Chunin were proxies. They carried out the order of their Jonin and also protected their identity. Not even Genin were aware.

Genin were the normal ninja, the ones who went out to do the work. While this is a simplified way of putting it, the ranking system certainly supported anonymity even within the same group of ninja.

4 They Kept Their Skills Within The Family

Enemies would try to infiltrate ninja schools to learn their teachings. For this reason, many ninja passed down their skills through the family. Only family members were eligible. Therefore, children were born into the trade.

They were taught at a young age, comparable to the early training of the samurai. The children would train in such things as flips, kicks, and stealthy movements. It would be disguised as a game. If he was deemed worthy, the child would go on to train as a ninja. By passing it through the family, secrecy and loyalty were assured.

3 Ninja Did Not Seem Like Ninja

Ninja are portrayed as warriors dressed in black with masks over their faces. There has been no historical account, though, mentioning the use of masks. And the black outfits that look so conspicuous in modern times were normal garb in that era.

Still, many thought that ninja had some standard attire, just as samurai did. However, that was a warrior’s outfit. Ninja spent most of their time in normal civilian clothing.

To live among the people, they would blend in. They would pretend to be samurai, masterless samurai, or hermits. It was a ninja art to learn several skills outside of ninjutsu to convincingly fit a role. Knowing the culture, the hairstyles, and the mannerisms was as much—and more—a part of their infiltration techniques.

Tokugawa Ieyasu employed ninja as bodyguards. Instead of having them wear the attire of ninja, he had them masquerade as gardeners. It gave them a reason to stay close, moving through the palace grounds.

Their status also helped them remain obscure. Ninja could be anyone, such as nobility. Yet they could also be peasants. The sickle and chain was a tool partially inspired from their practice to convert farm implements into weaponry.

They did unheard of things such as make women warriors (kunoichi). They would sometimes use agents such as the young, the weak, or the dumb. Using such low tactics was unheard of by the samurai, and many cases of ninja went undetected during that era.

2 Modern Records Are Inaccurate

During the early 20th century, the ninja craze was rekindled. It would eventually move to Western lore. Authors penned historical accounts of ninja. Unfortunately, many were enthusiasts or hacks given over to dramatizing the ninja. Therefore, many inaccurate accounts of the history and skills of ninja exist.

The ninja hype of the 1950s and ’60s has also obscured the truth about ninja. Some “misconceptions” about ninja are blatantly impossible, but a few widely held misconceptions have even fooled authors.

In the past few years, new efforts have been put into trying to separate the lies from the truth. Part of this renewal of interest is because texts written by Japanese ninja have been translated into English.

Yet both old and new accounts differ. Some will claim that all ninja had a strong moral code, while others will claim that they had none. One will speak of throwing stars (which the ninja didn’t use) or how ninja didn’t use explosives (which they did). But there is a reason that the future of ninja lore will never be solved.

1 We Enjoy The Fictional Ninja More

This is the greatest reason why ninja will always remain history. Do people truly want to unravel the mystery of the ninja? Thousands of more accurate accounts exist, but they’re largely contradictory due to misconceptions that exist even within nonfiction.

The public at large is far more interested in the version of ninja they widely acknowledge as myth. They’re the ninja Bruce Lee is chopping down. They’re the Teenage Mutant Ninja Turtles.

A multitude of fictional renditions of ninja exist, and the truth is that people would much sooner watch a ninja movie than watch a historical film about ninja. We’ve accepted being lied to, but would the ninja of the past mind it?

They would likely consider it a greater tragedy if their mystique was conclusively unraveled.

Kellie is a list enthusiast who works as a freelancer. Follow her on Twitter.

What started as a parody of literally every trope in ’80s comic books has become a juggernaut of a franchise, with no signs of stopping, even 36 years after their 1984 debut. The Teenage Mutant Ninja Turtles have been adapted into cartoons, movies, comics (so many comics), board games, video games, and probably every kind of merchandise you can possibly think of. 

Here are 10 amazing facts about the Teenage Mutant Ninja Turtles.

10. Their First Issue Sold Out in 1984

The success of the Teenage Mutant Ninja Turtles (or TMNT) is practically a rags to riches story. Turtles co-creators Kevin Eastman and Peter Laird both contributed to art and story. The original Turtles comic was never intended to go beyond a single issue, and this is evident by the fact that the main villain, the Shredder, dies at the end of the issue (spoilers!).

The duo printed off a small, 3,000 copy run of the comic using money from a $500 tax refund and a loan from Eastman’s uncle. After printing, they had just enough money to run an ad in Comics Buyer’s Guide Magazine, and to Eastman and Laird’s surprise, they sold out within several weeks. That wasn’t the end, either, as more orders came in, they were compelled to produce another 6,000 copies of the book.

The two realized that they might have been on to something big, so they got to work on a second issue, introducing many elements that would come to define the Turtles universe. As soon as they had issue 2 finished, Mirage Studios had orders for 15,000 copies, issue 3 would sell a massive 50,000 copies, and sales would continue to skyrocket, until issue 8 sold 135,000 copies, rivaling some of the best selling comics in 1985 (like Uncanny X-Men).  

9. The Turtles Came from a Simple Sketch

It might (or might not) surprise you that the Ninja Turtles were created in 1983 as a joke. Eastman and Laird were struggling illustrators, sharing a studio apartment about the size of a living room. 

One night, Eastman drew a turtle standing upright with nunchaku strapped to its arms and a bandanna wrapped around its head. Eastman wrote “Ninja Turtle” above his sketch and handed it off to his partner, hoping that it would make him laugh. 

Laird was so amused by the drawing that he started his own, more refined drawing. This kicked off a competition between the two artists, eventually resulting in the character designs that appear in the first issue.

The next day, they both looked at the drawings they’d created and decided that they just had to write a story to go with their designs. 

8. Mirage Studios Wasn’t a Real Company

Mirage Studios got its name because of the fact that (at the time of the first issue’s publication) it wasn’t a real company and Eastman and Laird’s studio consisted of their tiny studio apartment. Peter Laird described the space as only having kitchen tables and couches with lap boards. 

After the success of the first issue, Mirage would become a real company (adding further irony to the name) and would move to Sharon, Connecticut, where it would stay for two years before moving again to Northampton (a place that appears often in Turtles cartoons, comics, and the first movie). 

The company would also foster the careers of many underground cartoonists when the senior staff (Kevin and Peter) stopped being able to work on actual comics due to the complications of running the media empire surrounding the Teenage Mutant Ninja Turtles. 

7. The Turtles Exist Within the Daredevil Universe

The origin of the TMNT parodied at least four tropes popular in 1980s comics. Ninjas (like Daredevil and the enemy that he fights, “the Hand”), mutants and teenagers (popular in comics like X-Men and Spider-Man), and of course anthropomorphic characters (like Dave Sim’s Cerberus the Aardvark). 

To add to the hilarious parallels to comics that were popular at the time, the origin of the Turtles directly referenced the origin of Daredevil. In the origin of the TMNT, a blind man crosses a busy New York street, walking into the pathway of an oncoming truck. 

A young man (who is supposed to be a young Matt Murdock, aka Daredevil) rushes forward and pushes the old man out of the way. The truck swerves, crashing and causing a canister filled with radioactive ooze to strike a glass terrarium held by a little boy on the side of the street, freeing four baby turtles in the process. 

The Turtles end up in the sewers covered in ooze, where their future mentor Splinter (who was watching the whole thing while doing some dumpster diving) would gather them up in a coffee can, getting the ooze on himself in the process and mutating them all into humanoid creatures.

The parallels to Daredevil do not stop there. As mentioned earlier, one of Daredevil’s main enemies was the mysterious organization of criminal ninjas, “the Hand.” Well, the Turtles had their own criminal organization of ninjas as well, called “the Foot.” Additionally, Daredevil was trained in the city by a man named Stick, and the Turtles were trained below the city by Splinter.  

6. The Turtles Craze in Europe Caused an Ecological Disaster

Due to the popularity of the Ninja Turtles, kids in the UK in the late ’80s and ’90s not only stripped store shelves of every TMNT toy they could get their hands on but also caused the demand for red-eared terrapin to explode.

Red-eared terrapins are not native to the UK, and as you might imagine, due to the facts that these turtles can grow as large as a whole foot (no pun intended) and turtles are not very easy to care for in the first place, most of those turtles ended up being abandoned in ponds instead of getting new tanks (a fact that is as heartbreaking as it sounds).

This caused what amounts to an ecological disaster. Red-eared terrapins eat a variety of things, including ducklings, small waterbirds, and other amphibians. This can cause damage to the balance of life and waterways where they’re introduced, and that is exactly what happened in Europe.   

5. The Word Ninja Was Banned in Europe

Turtle fans in the UK were treated to a slightly different version of the cartoon that was making waves throughout the US in the late ’80s and early ’90s. The name of the show was changed from Teenage Mutant Ninja Turtles to Teenage Mutant Hero Turtles. 

The reason for this change was due to censorship policies in Europe. Censors in Europe thought that the word ninja was just too violent for a show aimed at children. Thus, every piece of memorabilia, every toy, and every other product to bear the name of the Turtles would feature the word Hero instead of Ninja.

Little did these censors realize, the collective shock that would come to European Turtles fans when the internet came along and revealed the fact that they had been lied to throughout their entire collective childhood.

Oh, and they replaced Michelangelo’s nunchaku with a weird grappling hook that looks like a yo-yo. It was apparently illegal for them to show a pair of nunchakus on screen.

4. The Turtles Used to Have Tails

In the original comics and designs, the Ninja Turtles were based on red-eared sliders (hence why they were so popular with kids in Europe), and they were also designed with tails.

The road to marketing the Turtles to toy companies was difficult, and the property was turned down by every major toy company in the ’80s, but Playmates Toys would finally take a chance on the property, a decision which would skyrocket the company to new levels of success.

During the early design process, playmates created a prototype sculpt of the Turtles. This sculpt featured a tail that looked more than a little phallic. 

The design was revised without the tail, and this design choice would be echoed in every Turtles property for the next three decades. 

3. Their Arch Villain, the Shredder, was Based on a Cheese Grater

Every great comic book character needs an arch-nemesis, and it might surprise you to find out how the TMNT got theirs. 

After a night of drinking, Kevin was drying dishes when he came across a triangular-shaped cheese grater. For some reason, Eastman decided to put the grater on his arm and turn to Laird, saying, “Could you imagine a character with weapons on his arms like this?”

The name Kevin came up with was less than amazing, though, calling his creation “Grate-Man.” Fortunately for all of us ’80s kids, Peter Laird suggested the name “the Shredder” instead. 

So, yes: the Shredder, the most feared enemy of the Ninja Turtles, who leads an army of ninjas in New York City that strike fear in the hearts of the criminals they work with, was named after a cheese grater.

2. The TMNT Led to a Wave of Knockoffs

Thanks to the popularity of the TMNT, both toy companies, and production companies behind children’s cartoons looked at the heroes in a half shell as a golden opportunity to create insanely popular toy lines and cartoons themselves.

As many as 20 knockoff cartoons and toy lines have been made, each following the same formula as the Teenage Mutant Ninja Turtles, but without the same levels of success that the Turtles have seen.

A few especially terrible ones include Street Sharks, Biker Mice from Mars, and Wild West C.O.W.-Boys of Moo Mesa (which centers around three teenage cow… boys, who protect their town from all kinds of bad guys). 

Of these three, Biker Mice from Mars lasted the longest, followed by Street Sharks (which lasted from 1994 to 1997), and Cowboys of Moo Mesa was the biggest flop of the bunch (only lasting one year).  

1. The TMNT Toy Line Changed the Action Figure Market

As was mentioned earlier, Playmates Toys was the only company willing to take on the Teenage Mutant Ninja Turtles. Other toy companies thought the concept was too ridiculous to fly with kids or parents. 

But you may be surprised to learn that Playmates Toys specialized in making dolls at the time. They had no experience in the boy’s action figure market. Despite this, Playmates would gain massive success after deciding to push forward with the TMNT action figure line despite a less than enthusiastic unveiling at the 1988 New York Toy Fair. 

After an initial 3,000 piece order, the Turtles would go on to become one of the most significant success stories in the toy industry and many fans of the line consider it to be the true start of a trend in 90s action figure lines. 

By 1990, the toy line was one of the most successful in the industry’s entire history, making $200 million in that year alone and taking up at least 60% of the action figure market.