VOL.214 APRIL 2026
THE APPEAL OF YOSHOKU: JAPANESE-STYLE WESTERN CUISINE (PART 2) [Introducing Precious Traditional Japanese Culture to the World] The Training of Japanese Swordsmiths: Passing Down the Inexpressible Craft

Johan Leutwiler, the first katana-kaji, or swordsmith from outside Japan, works on an ongoing basis to craft Japanese swords. We spoke with Johan about how the art of sword-making is passed down, and what significance the apprenticeship holds, based on his own experiences.  

The training system to become a katana-kaji is quite unique compared to apprenticeship for other crafts and professions. Since a master and an apprentice spend so much time together under the strong bond of the master-apprentice relationship, mutual reliability and compatibility between them are an extremely important, even before acquiring technical skills. A good relationship between both parties is absolutely essential.

Training to be a swordsmith takes at least five years. One does not start making swords immediately upon entering the apprenticeship. In most cases, it takes three years before apprentices begin taking part in sword-making in earnest. The first three years primarily involve cleaning the workshop, performing miscellaneous tasks, managing tools, crafting small accessories, and assisting the master. This period is spent learning the fundamental skills while building practical ones. Since a master’s swords are often traded for several million yen or more, apprentice is not entrusted to assist with actual sword-making until a certain level of skill has been acquired. Even after beginning to take part, an apprentice constantly works under immense pressure and tension.

The manner in which skills are passed down is also distinctive. In general, a master rarely provides detailed instruction to an apprentice. The expected approach is to watch and learn, that is, to “steal” master’s techniques. Apprentice observes the crafting the master performs on a daily basis, and acquires skills through constant reflection and trial and error.

Also, there is no labor union system in place to guarantee apprentices’ status or working conditions, and training environments vary greatly from one workshop to another. While some are fortunate enough to work in positive environments, others are required to endure excessively demanding conditions. In light of these circumstances, the most important thing is for apprentices to persevere patiently, steadily refine their skills, and cultivate the ability to forge swords independently after they have left their master. When they strike out on their own, perseverance and resolve are the only things they can rely on. That is why I believe apprenticeship is not a period of being taught, but rather the time it takes to learn to stand on one’s own feet.

Behind the seemingly romanticized world of sword-making lies the steady accumulation of daily efforts and a harsh reality. The path of the katana-kaji apprentice is by no means an easy one. Even so, many dedicate themselves to this world to carry the traditions of Japanese sword crafting into the future.

Completing a Japanese sword involves a number of different processes. These include tanren (forging or tempering),¹ hi-zukuri (smith forging),² yaki-ire (tempering or quenching),³ and finally, shiage (finishing). Each step is indispensable, and every single one significantly influences how the finished sword turns out. This is a world in which the slightest delay in making a snap judgment or lapse in concentration — regarding the intensity or temperature of the fire, the hammering technique, and so on — is directly reflected in the finished product. What is required is the ability to maintain constant focus and work without losing concentration for even a single moment.

During my apprenticeship and early days as an independent swordsmith, my technique was inconsistent. Things rarely went as planned, and failure resulted in a loss of materials and time. Considering the immense responsibility for each sword, the daily pressure and stress are by no means insignificant. Looking back now, though, I believe that tension drove my growth. “What can I do to improve the next one?” — constantly pondering this question became my natural approach to training.

There is no final stopping point in learning the craft of sword-making. No matter how many blades I forge, I never feel that “this is good enough” — I always identify the next challenge to take on. Yet, continuing down this path without a set goal in mind is also precisely what makes the work of the katana-kaji so fascinating.

Modern swordsmiths study and refine their craft by modeling their work on the masterpiece swords crafted during the Kamakura period (late 12th to early 14th century), an era when the “perfect form” of the Japanese sword is considered to have been established. However, the exact methods used at the time are not documented in detail. What materials were used? What exact processes were involved? Without precise answers to such questions, we must continue to search and explore on our own.

During nearly 700 years after the Kamakura period, the techniques, materials, and environment have changed significantly. What is considered “common sense” today may not have been so in the Kamakura period. That is precisely why we cannot rely solely on techniques we have been taught, and we cannot trust solely in current established theories either.  We must constantly ask ourselves whether this is truly the best way, whether there are alternatives, and whether this is indeed the correct solution, while continuing to think deeply and refine our methods day after day.

Some techniques may have been lost over the course of those seven centuries, while other innovations have not yet been discovered. I believe that recreating a legendary sword from the past is not merely about realizing a similar shape, but about rediscovering the very techniques originally employed to create it. My approach is to search for those discoveries as I face the work of crafting another sword on this day.

Johan Leutwiler
Born in Switzerland. Seeing Japanese swords at an exhibition at age 17 and being captivated by their beauty inspired his aspiration to become a swordsmith. After coming to Japan in 2017 and training as an apprentice for five years, he became the first foreigner to obtain national certification as a katana-kaji in 2024. After becoming an independent swordsmith, he established a workshop in Hiroshima Prefecture and received the Achievement Award (First Place) and New Face Award in the Sakuto (Blade Forging) division at the 2025 Contemporary Swords and Artworks exhibition. His swordsmith name is Mitsutsuna.
Photo: KUDO Asuka

• 1. The process of hammering and forging (or tempering) metal. The objective is to remove impurities and homogenize the carbon content by hammering the metal to flatten it more thinly and repeatedly folding it over.
• 2. The process of heating metal and applying force to transform its shape. Also called tanzo.
• 3. The process of rapidly cooling metal that has been heated to high temperatures in water or oil to harden it.

By Johan Leutwiler
Photo: KUDO Asuka