A Ko-Ichimonji Sukeyasu Tachi (古一文字助安)

This 800-year-old tachi from the Ko-Ichimonji school occupies a rare and precise moment in Japanese sword history: the transition from the restraint of the Ko-Bizen tradition into the more exuberant world of the Fukuoka-Ichimonji school. Early works from the opening years of the Kamakura period (1184-1222) are classified collectively as Ko-Ichimonji, and this blade is an exemplary piece – retaining Ko-Bizen characteristics in its shape and jiba while introducing the tell-tale ko-chôji (small clove blossom buds) that signal something new beginning to emerge.

Unlike the great majority of tachi from this era, which were heavily shortened over the centuries and lost their signatures in the process, this sword has been only moderately reduced, preserving the two-character mei Sukeyasu on the suriage nakago. The first character, 助 (Suke), is clearly legible; the second, likely 安 (yasu), is more challenging to read and the NBTHK have left it open to interpretation. No documented records of a Ko-Ichimonji smith named Sukeyasu are known, making this possibly the only surviving example of his work. The characteristics of the blade strongly suggest he worked in close association with Ko-Ichimonji Sukenari.

The blade is remarkably healthy for its age. The jihada is a beautifully active itame mixed with mokume and nagare, with abundant ji-nie, vivid chikei, and a deep, spotted jifu-utsuri that lends the body of the blade an icy-blue quality under light. The hamon is a nie-laden ko-midare-chô enriched with ko-chôji, ko-ashi, yô, kinsuji, sunagashi, and yubashiri running parallel to the yakigashira. The graceful koshi-zori curvature flows dramatically into the stout nakago – a feature that most heavily shortened tachi have lost entirely. This is a sword for the serious connoisseur, a rare and historically significant reference piece from one of the most important transitions in the Bizen tradition.