Sugawara Sogo Budo Institute “Nihonto Research and Discussion”

(informal unofficial English translation) 

What Koryu Sword Handling Techniques Might Teach Us About the Origins of the Nihonto

Making an inference from the way the Nihonto is gripped

This is the first of a series of articles relating to the research and discussion of the Nihonto. This article addresses some considerations regarding the connections between the handling of the Nihonto and the Nihonto’s origins.  

The author has, for a long time, devoted his study to Tenshin Shoden Katori Shinto Ryu.  Katori Shinto Ryu is one of three source styles for all Japanese kenjutsu and is one of the oldest koryu martial art.  It is possible to see that the many fundamental techniques of the style reflect the nature and characteristics of the Nihonto. For example, let’s take a look at the most basic of the style’s techniques: how to hold the sword.  

When a swordsman handles a sword, it is a basic understanding that the body and sword must become one.  On this point, the grip on the sword is crucial, and it would not be an overstatement to say that the handling of the sword begins and ends with the grip.  The Nihonto is gripped with two hands, and the grip on the right and left hand should be held with particular attention to the middle finger and thumb.  The space between the right and left hands should be the length of one grip.  This type of gripping allows for changes in the way the sword is held to execute the various techniques.  

To properly grip with the left hand, in Katori Shinto Ryu the tsuka-gashira (handle butt) is initially placed on the palm, and then the hand grips the sword as if wrapping the handle.  This is called the “handling technique of holding an egg.”  Gripping the sword in this way prevents it from slipping out of the swordsman’s hand.  In addition, and as relevant to this article, this type of grip may shed light on the origins of the Nihonto as well.

The Development of the Nihonto and Handling it with One Hand

In ancient times, Japanese swords were generally straight and/or double-edged.  From the Heian Period to the Kamakura Period, the curved tachi appeared.  The tachi then evolved into a less curved sword, which served as the basis for the standard Nihonto.  It is likely that one of the reasons for the deep curve on the tachi—which was quite long and used from horseback—was to prevent the kissaki from hitting the ground.  Because the swordsman needed one hand to hold the harness on the horse, the tachi also had to be light in order for him to manipulate the weapon with the other hand.  Overall, tachi are relatively skinny.  While there are some tachi that are wide toward the pommel and thin toward the kissaki (this style of sword being known as “Funbari”), this might be for purpose of adjusting the balance of the sword.  

When the tachi (use on horseback) evolved and became the Nihonto (use on the ground), swordsman compensated for the lack of momentum, which would have been previously available when striking from horseback, by holding the sword with two hands. With respect to the curvature, it remained a characteristic of the Nihonto so that the swordsman could control force.  Notably, one could see evidence that the tachi was handled using one hand by looking at the nakago (tang).  

Historically, one-handed short swords have a nakago of about the length of one hand.  In Europe, the length of the nakago and the length of the blade usually have a predictable range of ratios (either 1:1, 1:1.5, or 1:2). Similarly, too, Japanese blades can be examined by looking at the length of the nakago.  

Tangentially, the preferred length of the blade for Nihonto should be seven hand lengths.  In Japanese myth, the Totsuka blade is an example, but even the famous Shichie blade located at the Isonokami Shrine is so called because, the author thinks, the blade is seven (“shichi”) hand lengths long.  

In any event, there is the example from World War II, where many of the Nihontos that were brought to battle suffered broken tsukas (handles).  These Nihontos were old swords (heirlooms) that actually had the nakago length of a one-handed sword.  Thus, when they were fitted with a tsuka meant for two-handed use, this resulted in the tsuka breaking.  Notably, the swords made during the war have nakagos that are much longer and thus appropriate for two-handed use.  

The Influence of the Great Straight Sword, the “Sukanto”  

The old one-handed and double-edged straight sword evolved into the curved Nihonto, and this progression may have been largely influenced by the Emishi who lived in the northeast part of Japan and used a “Warabite”-type sword (the author believes the Warabite sword was influenced by Balkarian and Cossack traditions), and the Chinese who already had developed a very large sword called the Sukanto.  

In Japan, archeologists have found many large straight-swords dating back to the Kofun period, and it is believed that these swords — which appear related to the Sukanto — entered the country through the silk road.  The Sukanto in this article is a picture of an artifact preserved in Japan, and the author has been to the museum to see and observe the sword.  

Because the Sukanto is heavy, it is believed to have been handled using two hands.  The left hand, however, is believed to have wrapped the round end of the sword during this two-handed use.  This type of grip reduced the shock to the swordsman when hitting hard objects such as armor.  

This type of handle design could actually be seen in earlier metal swords (called Akinakes or “Akinak” in Russian) used by the cavalry of the Scythian culture.  The metal swords are believed to have been used from 300 BC; before then, bronze was used, and going back further in time bone was used.  Interestingly, the bone swords were constructed from the animal’s leg (from the knee down), and the bone swords had a handle butt that looked like horns.   

The horn-ended handle could be seen in the Bronze Age as well, but as armor technology advanced, the sword would bounce back at the swordsman upon a strong strike.  Thus, the end of the handle changed from horn-shaped to round-shaped, and the swordsman resolved the shock issue by wrapping the left hand around the round end of the handle.  

The Sukanto is essentially a large sword that inherited the round handle-end, and the Sukanto and the curved Warabite sword (used by the Northeastern Japanese) merged to create a new sword called the Ryugozukato.  

When gripping the Sukanto, the round part of the metal handle would result in the skin ripping when used in cold weather.  Thus, in Japan, the round end of the sword was replaced by a wooden handle.  Still, the way a swordsman gripped the sword by wrapping the left hand around the butt-end of the handle persisted and was inherited by later generations of swordsmen.  

The Origins of the Curved Sword and the Shape of the Nihonto

It is said that the curved Nihonto began to appear during the mid-Heian period, but it is difficult to tell how this change came about.  

The tradition of curved swords could be seen in Europe.  Between Islamic Turkey and Christian Rome was a place called Hazal (Japanese phonetic) that was created around the 6th Century.  The swords from Hazal were double-edged and mostly straight, but the blade was slightly curved up at the tip.  

The picture of the Hazal sword in this article was taken by me at the Caucasus Research Center. I also went to Ukraine and visited the Zaporozhye Military Museum, and I was particularly taken by the researcher there who told me that the Hazal sword looks very similar to the Nihonto.  

The Hazal swords have been found in Russia near the northern waters of Japan, so we can tell that it traveled on the silk road and was a fairly common weapon that spread to many areas.  In Japan, however, the Hazal sword has never been found.  Japanese swords are curved all the way, and even the “Kotorimaru” sword — which is a curved, double-bladed sword — is curved all the way to the handle. 

Swords outside of Japan usually have a handle that turns down (toward the blade), and Japanese swords that curve with the blade might be somewhat of a rare characteristic. This characteristic, however, is actually common among weapons used by the Ainu people (native Japanese).  

In the latter part of the seventh century, the Warabite sword began appearing in Japan. In the beginning, the Warabite sword was also straight, but the handle was curved and one could discern the origins of the curve in the sword.  Professor Ishii examined the Warabite sword from nationwide samples and divided them into three categories.  

The Warabite sword adopted the curve at the end of the eighth century.  The Warabite swords were mostly found in the northern part of Japan (southern Hokkaido), and from this Professor Ishii believed that the Ainu people must have developed the Warabite sword; however, this theory is not accepted in the mainstream literature.  

In 2005, the author showed a book to the Nordic (Japanese phonetic) state museum, and the researcher from the Caucasus who accompanied me saw an x-ray picture of an Ainu sword and, surprised, said “this is Balkarian.”  The Warabite sword and the Ainu sword might have been strongly influenced by the Balkars tradition, and the author believes this to be so.   

Sabre and the Sword

Around the second half of the 10th Century, the European double-edged long sword took on a strong curve.  This development may have been influenced by the Persian swords, and in Russia that is the accepted understanding.    

In the Caucasus the curved longsword is called sabre.  Sabres were generally used from horseback, and their sword techniques included using the momentum of the horse to cut down an opponent, receiving and entangling enemy strikes, and spinning the sword with one hand.  For these reasons, the sabre had to be long, light, and well-balanced.  One can see the many similarities between the sabre and the tachi.  

Around the 15th Century, the Zaboroshue Cossacks (Japanese phonetic) used the “shashuka” sword (Japanese phonetic) that had a less extreme curve than the sabre.  Notably, the word “sabre” comes from the Cherukes (Japanese phonetic) words “seri” (knife) and “pura” (snake).  The snake supposedly represents the belief in Islam that one who goes to hell is attacked by a snake.  By contrast, shashuka means “longsword.”  

There is a reason why the Cossacks moved from using the sabre (with an extreme curve) to the shashuka (with a slight curve).  The shashuka allowed the swordsman to attack immediately from the draw.  This follows the same path of development as the “nukitsuke” in Japanese kenjutsu, which uses similar one-handed manipulation of the weapon as might be seen in western styles of sword combat.  

In Katori Shinto Ryu, the draw in the beginning-level iaijutsu may generally be interpreted as an attack.  In the advanced forms, however, the draw is a defensive technique that uses the “mine” (back) of the sword to receive/entangle/deflect.  The advanced forms, therefore, require the swordsman to draw one step faster than the opponent and are more difficult to execute.  

Using the Curvature in Kenjutsu

In kenjutsu, there are many techniques that use the curvature of the blade, such as entangling the opponent’s sword before attacking the neck, arms, or cutting up toward the opponent.  

Rather than for improving the cutting ability of the sword, it may be said that the primary purpose of the curve in the Nihonto is to allow the swordsman to receive an attack and deliver a counterstrike without damaging his weapon.  And this type of use is best done with two hands on the sword, particularly where the swordsman must be able to respond swiftly to an attack from various angles.  

Finally, the group of Cossacks who used the shashuka moved to Rostov-on-Don in Russia and is now known as the Don Cossacks.  They pledge their allegiance to Russia and also have the bushido spirit.                  

Special Series Part 4: Some Considerations on the Origins and Manufacturing Techniques of the Japanese Sword.  

Sugawara Sogo Budo Institute “Nihonto Research and Discussion” 

Considering the Potential of Casting and De-Carbonization Methods

Importing Sword Manufacturing Technology

(Informal Unofficial English Translation, Original Here)

Among the many facets of Japanese sword making history, one of the most interesting topics is the path in which the Nihonto evolved into its current, unique form. To understand this topic, one should consider the Kofun period (3-7thcentury).  During that time, the northern Mongolian tribe of Tatar influenced the development of the Warabite sword in Japan, and then swords such as the snake sword and the Chinese-type Sukanto, straight sword, and the Ento-sword entered Japan most likely through the Korean peninsula and based on the political situation at the time.  

The swords during this Kofun period can be largely separated into two groups.  First, the southern-type straight swords (China, southwestern Korea, Southeast Asia, and India).  Second, the northern-type curved swords (Aryan, Balkarian, Persian, Churuki, Mongolian Tatar, Korea, and Korean Gaya).  These two groups of swords can also be distinguished by their metallic makeup. 

The northern-type swords are made of soft, sponge iron, and the southern-type swords use high-carbon steel developed in China.  These two metals require completely different sword making methods. 

For sponge iron, the primary forging method is by folding the iron.  For the high-carbon steel, folding is not practicable so casting is the main method.  Then, once the sword is casted, the sword is de-carbonized to make it softer.  

A simple method of de-carbonization is to raise the temperature of the sword and then place the sword in water.  A more sophisticated method of de-carbonization is to place metals in a pot and gradually lower the temperature of the sword (the author experimented with this latter method, as will be discussed below).

According to the scientific journal “Nature,” seventeenth century Iranian sabers were made of special high-carbon metal called “utz,” which was developed in India.  The Iranian Damascus saber developed by Asad Ullah combined vanadium with other metals and repeatedly heat-treated the sword. The carbon structure of this sword is organized and formed into carbon nanotubes, as was discovered by an American research team.  

Nano technology is a field of study with vast potential.  Interestingly, the method of de-carbonization that manipulates the nature of the metal may even be considered as one form of nano technology.  

Unfortunately, the methods of ancient sword making are still a mystery and unknown.  Japanese swordsmiths, however, reject the casting method and do not even consider experimenting with it, claiming that casting was never an ancient method of forging a Nihonto.  Of course, a cast-made sword will not have the special characteristics and skin of a Nihonto, and such a cast-made sword would never qualify as a work of art.  Japanese smiths, therefore, see no reason to change the metallic makeup of the sword. The author believes that, so much as the metal is concerned, the Nihonto has not evolved much from the days of the Warabite sword that were prevalent during the Kofun period.

The World’s Oldest Steel? 

How were swords made 4100 years ago?  

Casted bronze and iron swords were developed around the same period, and some methods for creating these swords involved sandwiching the iron with bronze.  Welding techniques cannot be used for these types of swords, but the bronze was used to prevent rust.  This technique for preventing rust is unknown in the world of Japanese sword making, but a Damascus swordsmith from the Caucuses told the author that, until 300 years ago, such rust prevention techniques were used in the region as well.  The author then began to wonder whether this rust prevention technique may have inspired or led to the methods for manipulating the nano structures of the metal seen in cast-made swords.  

When the author visited the Caucuses, he held a rusted and damaged Damascus sword that could be bent 90 degrees and still return to its original position.  The author cannot speculate as to how this sword was made, but he is certain the metallic component of the sword is spring steel. Japanese swords are believed to be strong, difficult to bend, and razor sharp, but if one were to press the sword from the side (shinogi), the blade would probably bend relatively easily, and it is unlikely that such a bent sword would return to its original shape. When comparing the Nihonto with the Damascus sword, the author questions whether Japanese smiths should be satisfied with the current methods for making a Nihonto. 

The Development of the Forging Method                 

The folding method that is used in the making a Nihonto is probably some derivation of the forging method used in the making of a Damascus sword, but such a connection has not been acknowledged in Japan.  Tawara Kuniichi is the foremost authority on the scientific research of the Nihonto, and he examined ten straight swords from the Kofun period and separated them into three groups: (1) swords forged from one steel; (2) swords forged from two steels constructed vertically; and (3) swords forged from two steels constructed laterally.  Looking at the inset above, one could also imagine that additional forging methods were developed.  It’s possible that the forging techniques used to make the Warabite sword is relatively more advanced than the Kofun period swords generally.  The author believes this to be the case because of the influence of the Damascus sword; however, currently there is no way to confirm this belief.  

Throughout its development, the shape and forging techniques of the Nihonto evolved and improved, but there seems to be little advancement on the point of changing the metallic structure of the steel (as in the case of, for example, the Damascus sword). There is not the use of the sophisticated method of de-carbonization; rather, the Nihonto begins its carbon content at around 1.5%; the steel is folded about 10 times; and the carbon content is lowered to about 0.7%.  Beyond these generally set parameters, there is no further advancement or evolution of technique.

After WWII, Nihonto were prohibited by GHQ, and later returned as art pieces.  The ancient methods of forging were long lost by then, and the modern methods of sword making are what remains.  There is a need to innovate.  

For example, the method of making a Damascus sword can result in unique markings on the skin of the sword that resemble a swirling pattern.  Japanese smiths, however, create skin patterns using different methods. It may be helpful to examine the skin patterns on ancient swords such as the Warabite sword and the Mogusa sword and consider the genesis of their forging methods.  

De-Carbonization Methods after Casting

Considering the possibilities of the casting method, the critical element of such sword making is the de-carbonization methods.  As discussed above, there are two such methods.  

First, the water method.  This is the simplest method and thought to have been used for forging swords in China. Once the cast is made, the sword is heated and quenched in water, resulting in de-carbonization.  The de-carbonized sword can now be struck, folded, and forged.  While this method does not create unique skin patterns on the sword, the metal can be combined with low-carbon steel and folded together to create the skin patterns seen in a Damascus sword.  In Korea, this method is already used to create a Damascus-style Nihonto.  This kind of Nihonto, however, is too heavy for practical use. 

Second, the slow method.  In order to examine forging methods, the author did two experiments using a pot.  

The initial experiment tested de-carbonization using the slow method and, with the help of the Iwate Prefectural Museum, the author discovered that the method resulted in a 50% reduction of carbon in the metal.  Based on this experiment, we determined how the Shichie sword in Isonokami shrine was likely forged.  The Shichie sword appears to be a folded northern-type sword, but the content of the sword shows evidence of the metal used in the casted southern-type swords. The Shichie sword was made in Korea in the seventh century, and shows that the de-carbonization method existed then. 

In the latter experiment, the casted sword was covered in clay, placed in the pot, and heated together.  The author speculated that the reason why the spring steel Damascus sword did not break was because of the silicon element.  The author expected that this latter experiment with the slow method would result in the silicon moving to the outside of the sword and would also prevent rust.  While the sword was not tested in extreme conditions, it appears the experiment was a success.  The carbon content was not tested, but repeating the process would likely result in the appropriate chemical reactions.  

Making a Damascus Sword

The author entered the forge of Hamzat Bachiev to learn the ways of forging a Damasacus sword. 

On this occasion, we used Soviet-era high and low carbon steels, as well as three other types of metals to create 11 layers of metal.  Notably, the three additional types of metals we used are also used to make filing tools.  

First, we filed down the outer part of the metals and made sure air could not get in between the metal pieces.  We then took a wire and tied the pieces together.  Second, as we moved on with our work, Master Bachiev told everyone to leave and gave the author an individual lesson on the secrets of his forging technique.  

Master Bachiev’s secret was in the fire.  Instead of recording the event on video, he told the author to watch the color of the fire. The bottom of the fire was about 1,500 degrees.  The 11 layers of metal must be left until the middle is about to melt, but if the entire metal melts than that is a failure.  Master Bachiev used a broom-like implement to spray water on the fire as he raised the heat.  He kept flipping the metal until each side was about to melt, but he would not let any part of the metal reach the critical temperature.  Then, he forged the 11 layers of metal into one seamless piece. 

Master Bachiev only folded the steel about five to six times.  He said that folding the steel too many times would result in a skin pattern that is not as flashy as it should be.  Japanese smiths do not prefer flashy skin patterns, but the Damascus sword can be folded as many times as one prefers.  

Master Bachiev then cut the Damascus steel in two.  Next, he took two different tubes of steel, heated them, twisted them, and turned them into core pieces.  He sandwiched the core pieces with the Damascus steel and forged them together. At this point, Master Bachiev asked the author for any requests, and the author requested that unique “mokume” skin patterns be made on the sword.  Master Bachiev agreed, and he made 2 such patterns toward the edge and 3 such patterns on the back of the sword.  Notably, Master Bachiev used the folding technique itself to create these patterns.  

Is the Warabite sword truly a northern-style folded blade?  The Kofun period blades are rusted and difficult to discern their skin patterns, but it is possible that the Warabite sword might have elements of a southern-style casted blade.  Further research is warranted.  

The Fujiwara blade does not appear to have the unique skin pattern of a casted sword, but the related swords, such as those created by the Mogusa and Gassan schools, clearly have such skin pattern.  

The Gassan school is known for its “Ayasugi hada” skin pattern.  According to the shrine in Yamagata Prefecture, the folklore is that the demon Kiyomaru’s image is in Gassan’s skin pattern.  The historical records relating to the beginning of the Gassan school can be matched with records of the imperial household, and it appears the beginning of the Gassan school must have been during the Kofun period. 

Tangentially, “Gassan” sounds much like “Gasan,” which is a one of the Balkalian gods and even a name of a star.  In the Caucuses, there was a person by the sir-name of Gasan who owned a restaurant. In Russia, there are many people with the name Gasan.  

Recreating the Ancient Sword and Modern Challenges: 

As shown above, just like the Japanese hamon and skin, the Damascus sword also has similarly beautiful patterns.  Still, the Damascus-type swords, such as the ones being produced in Korea, are too thick and heavy.  How do we recreate the ancient Damascus swords that were light and essentially indestructible? The author suspects that we should examine the casting and de-carbonization methods.  

In the author’s opinion, the ideal sword is one that is a light, thin, curved, and has the flexibility and strength of a Damascus blade.  Modern smiths who forge blades for actual cutting do not experiment with making thinner blades.  Lighter blades are not preferred for test-cutting, and modern smiths tend to make swords that are thick, heavy, and weighted toward the tip.  

Another point is regarding the hamon.  The method of putting clay on the sword does not change the core of the sword.  A smith might experiment with other methods of hardening, including double-hamon and straight quenching.  

In experiments, the author was able to produce different types of hamon.  In November 2017, the author was in Washington, DC, and experimented with different hardening methods.  The blades used in the experiments are not polished, so the pictures here are those that were given a rough grind.  Unfortunately, the blades from this experiment do not show any activity in the skin.  

Ancient swords are not about their shape.  Rather, they are distinguished by their skin and the various activities in the metal that are produced from the hardening process.  Modern smiths cannot recreate ancient swords, and they might consider examining the development of swords during the Kofun period.  

The following may be said about the Nihonto: It is a product of a substantially developed and refined folding method, but the blade’s metallic structure has not evolved since the Kofun period because there has been no consideration or development of the casting method (which includes de-carbonization methods).