Ko-Hoki Yasuie

Ko-Hōki Yasuie and the Sword Culture of Hōki Province

Ko-Hōki Yasuie was a swordsmith active in Hōki Province (present-day central-western Tottori Prefecture) in the late Heian period (12th century). He is remembered in the history of the Japanese sword as a master representing the Ko-Hōki school. "Ko-Hōki" refers collectively to the group of swordsmiths active in Hōki Province before the Kamakura period, and Yasuie belongs to the line of Yasutsuna, who is regarded as its founder.

Hōki Province lies in the San'in region, and since ancient times it has been known as a place where high-quality iron sand is obtained from the Chūgoku Mountains. This abundant, high-quality material became the foundation of sword production in Hōki Province, and it is believed that by the late Heian period a group of craftsmen with advanced forging skills had already formed. Yasuie made swords within this environment as a smith of the line connected to Yasutsuna.

Yasuie's Style: Antique Elegance and Outstanding Craftsmanship

Works by Ko-Hōki Yasuie are valued as embodying the most classical beauty among late Heian-period old swords (kotō). The jigane is ko-itame mixed with jifu, with chikei. It resembles Ko-Bizen but is distinguished by a more pronounced hada and an overall blackish tone, and the whole is enveloped in the "antique elegance" of the hada peculiar to old swords. This textured quality of the antique hada is the product of forging techniques peculiar to the Heian period that are difficult to reproduce in later swords, and it is one of the main reasons Yasuie's works still receive exceptional acclaim today.

The hamon is ko-midare mixed with chōji, with ashi and yō well developed, and kinsuji appearing. The hamon edge has fine nie, and within the somewhat rough atmosphere peculiar to an older period, a sense of dignity can be felt. The bōshi is midarekomi with a slight hakikake, returning in a small round (ko-maru). Compared with the finely wrought Bizen and Sōshū works of later periods, Yasuie's hamon has a rustic simplicity, but it is precisely this simplicity that is highly valued as embodying the spirit of the samurai of the late Heian period.

As for sword form, many show the typical late Heian tachi form: deep koshizori, a large difference in width between moto and saki, and a small kissaki. This form corresponds to the fighting style of Heian-period warriors, centered on mounted combat, and has a functional beauty optimized for the motion of striking downward from horseback.

Lineage and Influence of the Ko-Hōki School

The Ko-Hōki school is formed as a group of swordsmiths centered on Yasutsuna, regarded as its founder, and including Sanemori, said to be his son, as well as Aritsuna and Yasuie. Above all, Yasutsuna, as the maker of Dōjigiri Yasutsuna (National Treasure), one of the Tenka Goken (the Five Great Swords under Heaven), is the smith who represents Ko-Hōki, and Yasuie made swords as part of his lineage.

The techniques of the Ko-Hōki school not only influenced later smiths of the San'in and Chūgoku regions but also became one of the wellsprings in the nationwide development of sword culture. Works of Ko-Hōki, which belong to the oldest category of late Heian old swords, are an indispensable point of reference in exploring the aesthetic and technical origins of the Japanese sword, and they are among the most important subjects of study for sword researchers.

Surviving Works by Yasuie and Cultural Properties

Extant works by Ko-Hōki Yasuie are extremely few, and their rarity raises the value of each individual blade. The only work with a confirmed signature is said to be one piece: the National Treasure tachi signed "Yasuie" (Kyoto National Museum), which was transmitted through the Kuroda family. This tachi has a graceful antique form with high koshizori and strong fumbari, is of excellent workmanship, and is also in sound condition.

TOUKENZA presents Ko-Hōki Yasuie as one of the oldest master smiths, positioned at the source of the Japanese sword. Its aim is to convey to contemporary enthusiasts and researchers the spirit of the Heian warrior embodied in these works and the finest of Hōki Province's forging techniques. Appreciating Yasuie's tachi is an experience of tracing back a thousand years of Japanese sword history and touching its origin directly, and its value is unwavering across the ages.