There are three main types of cords in Japan: twisted cords, braided cords, and Sanadahimo (Sanada braided cords). One single cord woven by Nepalese mountain people traveled across the ocean, became a spy tool for ninjas, supported the armor of samurai warlords, and eventually transformed into a "yakusoku-himo" (promissory cord) in tea ceremony, acting as a code to discern the authenticity of works. The way a cord is tied also serves as a password to indicate if someone has opened it. Isao Wada, the 15th generation Sanadahimo master, is now quietly beginning to unravel the techniques and knowledge of his family, which had been instructed "not to be revealed to the public" for 500 years. There are only two successors: himself and his wife. He hopes to preserve Japan's layered memories, embodied in a single cord, before they disappear.

#1 Twisted Cords, Braided Cords, Sanadahimo – Three Lineages Thriving in Japan

From the mountains of Nepal to the port of Sakai. Another history of Buddhism's transmission, traced by a single cord.

──Please tell us about the overall history of "cords" in Japan.

There are three common types of cords in Japan: twisted cords, braided cords, and Sanadahimo.

Originally, there was the twisted cord, made by twisting straw bundles or hemp threads in the same direction to form a single rope, like a hawser.

Ropes for yokozuna (sumo grand champions) and shrines have been used in various aspects of Japanese life since ancient times.

The second type, braided cords, originated in China and were introduced to Japan along with Northern Buddhism. However, they were limited to the imperial court, so common people had no opportunity to use them.

They were essentially cords for the imperial court. All braided cords are made of warp threads that run diagonally, so they stretch when pulled, and if one thread breaks, the entire structure collapses. This was a weakness.

That's why they were used as ornaments for court nobles who didn't engage in strenuous activities.

──And where did the third type, Sanadahimo, come from?

The origin of Sanadahimo is a cord called "Sanar" woven by Nepalese mountain people.

It was woven from yak hair, a long-haired cattle, and used to carry heavy loads in the mid-slopes of Mount Everest. It's an extremely durable and strong cord.

This traveled through the trade routes of Southern Buddhism and was concentrated in Luzon – what is now the Philippines.

Buddhist scriptures and *Indian sarasa fabrics were tied with sanar, and merchants from Sakai imported them whole to Japan. The contents were goods to be sold, but the cords were left at the port.

However, the Sakai merchants were very sharp-eyed, thinking, "This is incredibly strong; it could be useful for something."

But since sanar is made of *yak hair, the materials weren't available in Japan. It was only after the successful cultivation of domestic cotton in Higashi-Osaka that they were finally able to make it. Sanadahimo is the sanar cord made from cotton.

*Indian sarasa: Vividly multi-dyed cotton fabric originating from India.

*Yak hair: A premium natural fiber with excellent insulation and breathability, obtained from cattle living in the Tibetan Plateau and Mongolia at altitudes of over 3,000 meters.

──What are the characteristics of Sanadahimo weaving?

The number of warp threads is three to four times that of normal textiles. The weft thread is inserted and pulled tight to compress it horizontally, and then it is beaten with a reed to compress it vertically as well.

It's a special weaving method that gathers many threads tightly in one place.

To make the original single-layer weave even stronger, a double-weave (fukuro-ori) was developed in Japan. This made it strong enough to be used for tasks like pulling up stones for castle walls.

Twisted cords are stiff and round, so when used to lift a pillar, they tighten in a "line" and can cause damage. Sanadahimo, despite its strong tensile strength, is wide and tightens in a "plane," so it doesn't cause damage. That's why it was so valued.

#2 The Cord Sold by Ninjas — Koka Warriors and Iga Spies

The connection between Sanadahimo and intelligence, initiated by my ancestor Koremasa Wada.

──Please tell us about the connection between your ancestors and Sanadahimo.

Koremasa Wada was a warrior from Koka, and he was the lord of Wada Castle in *Aburahi.

*Aburahi: Refers to Aburahi, Koka-cho, Koka City, Shiga Prefecture.

Koremasa's biggest achievement was enthroning Ashikaga Yoshiaki as the 15th Shogun.

His elder brother, the 13th Shogun Yoshiteru, was assassinated by the Miyoshi family. Koremasa rescued Yoshiaki, who was a monk in Nara, sheltered him in Wada Castle, and eventually brought him to Nobunaga. He then ascended to Kyoto with Nobunaga and became Shogun, according to historical accounts.

──How did Koremasa Wada connect Sanadahimo with ninjas?

Koremasa was given the title "Lord of Iga," and he essentially managed the Iga ninjas. That's when he started having the ninjas make Sanadahimo.

Iga people would blend in among the itinerant merchants selling Sanadahimo. Since it was an unusual cord, they could easily gain access to castles.

There, they would gather information on the lord's health and local conditions. Their job was to bring back intelligence and money to the Ashikaga family, reporting to Koremasa.

Through this merchant route, the cord also reached the Sanada family in Nagano. And Sanada Masayuki, a famous warrior known as the most cunning strategist of the Sengoku period, was the first to use Sanadahimo for wrist and ankle bindings on his armor.

Braided cords were often used as a status symbol for those with official ranks, but they would stretch and break during battle. However, tying wrists with Sanadahimo acted as a fist support, and tying it around ankles could prevent bleeding. It is said that the name "Sanadahimo" was given because he was so successful in using it.

──Sanadahimo was also an important tool for ninjas, wasn't it?

Ninjas walked around disguised as merchants, so they didn't carry *chain mail or black outfits. Their luggage only contained rolled Sanadahimo and tools.

When infiltrating, they would wrap this cord around their arms and legs and insert bamboo splints to create makeshift armor. If wrapped around the head, the high strength of Sanadahimo, made with a double weave, would stop a sword from penetrating.

Since no metal was used, it made no clattering sounds. They could truly infiltrate in silence.

*Chain mail: A form of protective armor made by linking small metal rings together.

──What kind of intelligence activities did ninjas actually engage in?

In dramas, it's often brutal, but in reality, it's like today's spies, scheming behind the scenes when they want to bring someone down.

For example, they might replace the contents of an item that an important person is presenting to the lord, so when the lord opens it, something entirely different is inside. The lord would be enraged, and that person would fall from grace. Creating such situations was the work of ninjas.

As for whether there are any striking anecdotes, well, if they left behind anecdotes, they weren't good ninjas. The basic principle is to do their job without leaving any traces, so if there are records, it means they were clumsy as ninjas.

#3 Cords as IDs, Knots as Passwords

Sen no Rikyu's cipher system for "promissory cords," transplanted from samurai etiquette to tea ceremony.

──I heard that Sanadahimo has a deep connection with the tea ceremony.

In imperial court tea ceremonies before Rikyu, lacquered boxes tied with braided cords were used. When Rikyu tried to popularize tea among common people, such elaborate settings were not suitable for them. That's when "kiribako" (paulownia wood boxes) were conceived.

Boxes with braided cords had tassels hanging from the lid. This was a display of aristocratic extravagance, suggesting "more than enough." Rikyu's kiribako, on the other hand, had everything contained within the area of the lid. This reflected the Zen philosophy of "restraint in all things."

──What exactly is the "promissory cord" used for those kiribako?

Originally, the sageo (cord for a sword scabbard) of samurai had a family crest, and when swords of fallen warriors were collected and brought back, the cords helped identify whose they were.

Rikyu incorporated this into the world of tea as the promissory cord.

*Omotesenke, Urasenke, Mushanokojisenke – each has a designated cord pattern. The main Omotesenke has a plain cord. *Kama-shi (kettle makers), who produce heavy items, would make the central line thicker to indicate that heavy objects were inside.

*Omotesenke, Urasenke, Mushanokojisenke: Schools of tea ceremony founded by Sen no Rikyu. Omotesenke is one of the representative schools that faithfully preserves the spirit and forms of "wabi-cha."

*Kama-shi: Craftsmen who make tea ceremony kettles.

It signifies, "Be careful, there's something heavy inside," and was used to identify heavy items in a storehouse.

The cord for the Yabuuchi school, another tea ceremony tradition, is very simple with black and white, but black is the color of a samurai's court attire. The white line in the middle is the white afterimage seen when *kaishaku (the second in a seppuku ritual) brings down the sword.

*Kaishaku: The act of beheading a person who has committed seppuku (ritual suicide) at the moment they stab themselves in the abdomen, to shorten their suffering.

It means that while you are safe within the tea ceremony, you never know when your life might end once you step outside. Therefore, it conveys the message to future generations to devote themselves earnestly to tea while they are inside.

──I heard there's even a system to distinguish the authenticity of the cords themselves.

Because Sanadahimo is woven by compression, only the warp threads are visible as the pattern. The weft threads are not visible. This allows for a different color to be hidden in the weft.

When making the tassels, if that color appears, it's authentic; if not, it's a fake. Or, what appears white might actually be a nuanced pattern of pale pink and blue. It's like a code embedded within.

There are also various ways of tying knots, such as right-hand knots and left-hand knots. If a ninja were to replace the contents or insert poison and then re-tie it, they wouldn't be able to tie it correctly. This would indicate that someone had opened it. In modern terms, the cord's pattern is the ID, and the way it's tied is the password.

──You must notice inaccuracies even when watching movies and dramas, right?

In the movie "Ask Rikyu," there are cords of people who haven't even been born yet. In last year's historical drama, there was a Rikyu box placed in the Heian period.

When I wrote on social media, "That's not a kumihimo (braided cord)," they changed it to kumihimo halfway through. I was happy about that, but the cord holes for Sanadahimo were still on the bottom of the box.

We can't really enjoy movies.

#4 Beyond the Lockers of the Museum of Fine Arts, Boston – Moving to the US, Rebellion, and Succession

"For 500 years, stay out of the public eye." The resolve of the 15th generation to inherit a silent family business.

──Please tell us about your own upbringing.

I went to elementary school in Kyoto and junior high at a private school in Nara, but I was, as they say now, a school refuser. The future was already laid out for us.

Everywhere I went, people would tell me, "You'll be the successor." With my future decided, there was both a sense of rebellion and a fear of whether I had the skills.

One day, my father conspired with my school teacher, got all the visas and acceptance letters, laid them out in front of me, and said, "Go to America." A week later, I was already on a plane.

──What kind of experiences did you have in America?

The school had students from all over the world: sons of wealthy Arabs, sons of South American drug lords, sons of presidential aides. It was even more diverse than the differences between Kyoto and Osaka that I was used to. From then on, it was interesting.

Since my family's profession was this, my strongest subject was art. My teacher entered me into a competition without my knowledge, and I won first place in Pennsylvania, then the East Coast finals, and received the "National Finalist" award.

I was invited to the affiliated school of the Museum of Fine Arts, Boston, and with my student ID, I could enter the storage rooms. I would open a locker and stare at the "Fujin Raijin-zu" (Wind and Thunder Gods screens).

One day, when I opened a locker, there were Raku tea bowls piled up, exposed. Early pieces from the first to fourth generations. When I asked, "What about the boxes?", they said that when they bought them up after the war, they thought the packaging was trash and threw it overboard. I taught them over there, "This is the most important part."

──How has your learning in America been applied to Sanadahimo?

I learned about the "value" of colors in the States – the perceived weight of a color. For example, which stage of blue has the same weight as which stage of red?

This way of thinking was useful when making cords, deciding which colors to emphasize and which to blur. I also worked with jewelry, so I applied my knowledge of metal fittings, and that's how my current small accessories came about.

──What led to your decision to return to Japan and inherit Sanadahimo?

When I returned to Japan and visited department stores or participated in product exhibitions, almost no one knew about Sanadahimo. Even important figures in tea ceremony schools would say, "I didn't know that each family had a designated color."

I thought, if I quit, this culture itself would disappear from Japan.

Until then, for about 500 years, we were told "not to appear in public." This was to prevent counterfeiting. But that was when people knew about it and kept quiet, and as generations passed, it reached a point where no one knew.

If we remained silent, who would pass on the culture? So, since inheriting, I've decided to be open about it.

My paternal ancestors are from Koremasa Wada – a lineage of Koka warriors – and I was taught the etiquette of armor. My maternal ancestors were *nushi (lacquerers) and relatives of the Mushanokojisenke, tracing back to Sen no Rikyu.

*Nushi: Lacquerware craftsmen.

The stories of tea ceremony were passed down from them. Furthermore, we are also a family of *sashimonoshi (joinery craftsmen), so I am the 7th generation sashimonoshi and the 15th generation Sanadahimo master.

The old shop sign was "Sashimonoshi Kōnan." We couldn't use the name Sanadahimo. Kyoto houses are narrow at the front and deep inside. If you were hammering wood at the front of the house, the sound of weaving in the back wouldn't carry outside, so no one would notice.

*Sashimonoshi: Craftsmen who make furniture, boxes, and tea ceremony tools by joining wood with dovetail and mortise and tenon joints, without using metal such as nails.

#5 The World's Thinnest Weaving: Who Will It Reach?

What the 15th generation, without a successor, entrusts to the cord now.

──I heard that even weaving professionals don't understand the structure of Sanadahimo's double weave.

That's right. Even loom operators don't understand "how this happens." Normally, if there are two layers, a gap would open horizontally, but with Sanadahimo, because there are so many threads, when the weft is pulled, it's compressed and doesn't open.

Since it's woven in alternating upper and lower layers, the progress is twice as slow. The cost skyrockets, so normally, no one would do it.

──Please tell us about the actual weaving process.

You operate the heddles with pedals, insert the weft with a bamboo spatula, pull it tight, and beat it with a bamboo reed.

It's a continuous process. The tension applied is everything, so once one person starts, only that person can weave it. The same person continues for the entire 70-meter length until it's finished.

──I hear there are surprising patterns in the pattern books from the Taisho era.

There are patterns from when the first streetcars ran in Kyoto in the Taisho second year. There's a gray section at the bottom of the telephone pole and wire pattern. When I researched why, I found that old telephone poles had stone bases. They even realistically reproduced the stone part.

It was a pastime for wealthy people, who said, "I want a streetcar pattern." When I said my loom couldn't weave it, they funded me, saying, "I'll give you money, so make a loom and weave it when you can."

The finished product was made into a haori cord, shown to geishas with "Isn't this nice, it's a streetcar!" It was just a cord to show off.

The uses have also changed with the times. From tea ceremony tools to kimono fabric, and during the war, it was used for parachute cords and gaiter cords. The category changes with each era.

──You are also attempting to adapt ancient knotting techniques to modern life.

If you attach metal fittings to an arranged "myoga knot," which is used for sword sageo, it becomes an earring, and if you make it a necklace, you can also hang glasses from it.

Actually, I was only making necklaces, but a customer told me, "It's convenient for holding glasses." I leave the usage up to the individual.

Since Sanadahimo is woven by compressing warp and weft threads, it carries the meaning of "connecting people."

Some shrines give them out as charms, and some give them as charms for safe childbirth, wishing for "a strong child like Yukimura."

──I'd like to ask you frankly about the successor issue.

I don't have children, but traditionally, we weren't allowed to take on apprentices. There was a family rule that secrets would leak if outsiders were brought in.

Currently, there are only two Sanadahimo masters in this shop: my wife and I. If I die, there will be no successor, and this culture could be lost from Japan. All the data in my head would be lost as well.

I think I should write a book or something, but when it comes to promissory cords, there are businesses that make fakes, so it's a difficult situation. If I write carelessly, it could be used to create perfect fakes.

That's why I'm trying to tell these stories little by little. I hope you will listen carefully now.