The Smiths of the Yasukuni Forge: Profiles of the Master Craftsmen Selected from Across Japan and Their Enduring Influence
* Image is for illustrative purposes only.Table of Contents
What is the Yasukuni Forging Workshop — The Hand-Forged Japanese Swords Supported by the Military
In 1933 (Showa 8), the "Japanese Sword Forging Workshop" was established on the grounds of Yasukuni Shrine. Supported by the Imperial Japanese Army Ministry, this facility embodied a paradox—at a time when military modernization and mechanization were advancing rapidly, it deliberately manufactured traditionally hand-forged Japanese swords. It operated until the end of World War II in 1945 (Showa 20), producing approximately 8,100 swords in total.
The selection of swordsmiths was rigorous. Swordsmiths chosen through technical examinations from across the nation created swords under a multifaceted evaluation system assessing the quality of the jihada, the control of the hamon, and the beauty of the sugata. In the early years, the workshop operated on a rotation system, with selected swordsmiths residing on-site for several months at a time to carry out their work. As the facility's infrastructure improved, resident swordsmiths were stationed there, transitioning to a more organized production system. Most of the swords produced were delivered as military swords, though offerings to Yasukuni Shrine and ceremonial swords made to special order were also included, giving it a character distinct from a mere weapons factory. The Yasukuni Forging Workshop was built upon a delicate balance between meeting military sword demand and preserving traditional forging techniques.
The Swordsmiths Who Graced the Yasukuni Forging Workshop
| Swordsmith Name | Origin/Base | Characteristics and Accomplishments | Living National Treasure Designation |
|---|---|---|---|
| Gassan Sadakatu | Osaka, Gassan school | Inheritor of the "ayasugi-hada" long preserved by the school. A flowing pattern reminiscent of cedar wood grain was brought to the surface of the jihada through a technique that stands out for its individual character and high difficulty among methods of expressing jihada in Japanese swords. It is said that the characteristics of the Gassan school's work appeared particularly strongly in military swords that tended toward uniformity, and this lineage led to Gassan Sadatoshi | — |
| Sumitani Masamine (1921–1998) | Matsuai City, Ishikawa Prefecture (present-day Hakusan City), affiliated with Kaikoku Japanese Sword Forging Workshop (Onomichi, Hiroshima) | Still in his twenties when affiliated with the workshop, his technique already stood out. The "composite lamination" method he established after the war is a unique forging structure combining heart steel, skin steel, and blade steel in three layers, achieving both strength and flexibility, and is regarded as one of the theoretical culminations of modern swordcraft. The swordsmith himself stated that the roots of his technical thinking lay in practical experience at the Kaikoku Japanese Sword Forging Workshop | 1981 (Showa 56) |
| Miyairi Yukihira (1913–1977) | Sakashiro, Nagano | Records remain of his work as an army-commissioned sword craftsman, producing traditionally forged military swords. After the war's end, he dedicated himself to the revival of tatara steel-making and the reconstruction of Japanese sword culture, and after sword manufacturing was permitted in 1953 (Showa 28), he became a leading figure guiding swordsmiths throughout the nation | 1963 (Showa 38) |
| Takahashi Sadatsugu (1902–1968) | Saijo, Ehime Prefecture | He precisely controlled the komoji, gunome, and suguha hamon of the Bizen tradition, and records of his work at the Yasukuni Forging Workshop remain. He was the first swordsmith to be designated a Living National Treasure, and his achievement in reconnecting the technical lineage of the Bizen tradition after the war was significant. The Bizen-tradition blades he left behind have become important standard works for modern sword studies, allowing contemporary sword researchers to measure the standards of Showa-era blades | 1955 (Showa 30) |
The Goranto System — The Apex of Quality Control
The Yasukuni Forging Workshop possessed a unique quality control apparatus. Manufactured swords were evaluated and graded through examination by both army-related personnel and shrine-related personnel, and only works recognized as highest quality were enshrined and stored at Yasukuni Shrine as "goranto."
The selection criteria were stringent; swords had to meet a certain standard in every aspect—hamon, jihada, sugata, and polishing. This reveals an intention to maintain standards befitting Japanese swords as decorative craft objects, not merely as military equipment. Some of the surviving goranto are housed in Yasukuni Shrine's Yushuukan and Treasure Hall; when displayed to the public, they attract the attention of researchers as primary materials for Yasukuni sword research.
The Role of Traditional Technique as a "Wartime Incubator"
One of the historical significances of the Yasukuni Forging Workshop is that it became a place where forging techniques continuing from the pre-Edo period were practically inherited and refined at a time in the early Showa period when waves of modernization were bearing down. The hand-forging production process using tamahagane as raw material is fundamentally different from mass-production machine processing. Material assessment, adjustment of heating temperature, the number and direction of repeated folding and forging—all of this depends on the experienced intuition of the swordsmith.
In the forging workshop, multiple swordsmiths from different schools worked in the same space, naturally creating technical exchanges. The gathering in one place of the Gassan school's ayasugi-hada, the Bizen tradition's komoji hamon, and the forging techniques of the Yamato and Soshu traditions was a rare situation in terms of cross-school technical mutual influence. It was no accident that the foundation for producing multiple Living National Treasures after the war was laid here. The implicit knowledge shared among swordsmiths and their competition with one another lifted the overall level of technique.
Yasukuni Swordsmiths After the War — Moving to the Core of Reconstruction
Following the war's end in 1945 (Showa 20), Japanese sword manufacturing was completely banned by order of the GHQ. However, when the ban was lifted in 1953 (Showa 28), the swordsmiths who had gained experience at the Yasukuni Forging Workshop immediately resumed their activities and led the postwar Japanese sword world's revival.
Behind the ability to release high-level works immediately after the lifting of the ban lay the existence of forging workshop veterans who maintained their technical memory and sensibility throughout the prohibition period. The fact that two Living National Treasure swordsmiths, Miyairi and Takahashi, had connections to the Yasukuni Forging Workshop succinctly illustrates that the workshop functioned as a "wartime incubator" in Japanese sword technology.
They did not merely continue making swords. By training disciples, writing technical treatises, and establishing the academic foundation for sword research, they created the structural framework of Japanese sword culture as it lives in the present day. It would be insufficient to understand the Yasukuni Forging Workshop swordsmiths only through the lens of military sword manufacturing. As guardians who protected the technical continuity of Japanese swords—an intangible cultural property—during a tumultuous era, they deserve proper recognition. Many of today's young swordsmiths are inheritors of this lineage, and they continue forging swords today.
