The Test-Cutting Officials of Edo: Who Were They?

Yamada Asaemon was a hereditary title within a specialized occupational lineage granted the "tameshigiri goyō" (test-cutting official duty) by the shogunate during the Edo period. The family name was formally "Yoshichika," with successive generations taking the name "Asaemon." In official shogunate records, this role was called "otameshi goyō" and involved testing the cutting edge of katana on the bodies of executed criminals—a distinctly Edo-period institutional practice.

The first Yamada Asaemon is said to have been assigned the tameshigiri duty during the era of Tokugawa Iemitsu (the 1620s-1640s), and the family maintained this role for eight successive generations until its abolition in Meiji 2 (1869). The tameshigiri was conducted primarily at the execution ground in Edo's Kotsukahara (present-day Arakawa Ward), which also served as a site for fubun'ke (anatomical dissection), the two practices being inseparably linked.

The Birth of the Wazamono Ranking—Systematizing Blade Quality

The Yamada family's greatest historical achievement was the compilation and publication of the wazamono ranking. In Tenmei 8 (1788), the seventh-generation Yamada Asaemon Yoshichika authored a work called the "Kaihō Kenjaku," which for the first time systematically ranked katana by cutting quality.

The ranking adopted the format of sumo rankings—ōzeki, sekiwake, komusubi, and maegashira—making it easy for contemporary viewers to visually comprehend blade classifications. The highest rank, "ōzamono" (great exceptional blades), included smiths such as Osafune Nagayoshi, Horikawa Kunihiro, and Yasutsugi of Echizen, with lower categories of "zamono" (exceptional blades) and "ryō-zamono" (good exceptional blades) following.

What made this ranking system revolutionary was its claim to objectivity based on data from actual cutting tests on corpses, rather than subjective evaluation based on smith lineage or legend. The number of bodies cut—measured in categories such as hitotsu-dō (one body), futatsu-dō (two bodies), and mittsu-dō (three bodies)—became the standard for assessing cutting quality and exerted profound influence on subsequent concepts of blade value.

The Practice of Tameshigiri—Between Institution and Ethics

While tameshigiri appears cruel by modern standards, Edo-period society possessed a cultural framework that integrated punishment and post-mortem utilization. The bodies of executed criminals were semi-officially sanctioned for use in medical dissection (fubun'ke) and test-cutting, with the Yamada family monopolizing this institutional practice.

Blades to be tested were typically brought to the Yamada family by sword dealers and samurai families who commissioned the work. The Yamada family would test the blade and issue a "tameshi shōmon" (test certificate) documenting the results. Blades bearing such certificates increased in market value, and the phrase "Asaemon-approved" became a mark of trustworthiness in sword commerce.

However, the reliability of these certificates was sometimes questioned. During periods when corpses were difficult to obtain, tests were reportedly conducted on fresh wood or substitutes. By the late Edo period, forgery of "Asaemon certificates" had become widespread, making authenticity assessment a serious problem.

Relations with Sword Dealers—Function as an Authorized Appraiser

The role of Yamada Asaemon extended beyond tameshigiri, positioning the family as something akin to an "authorized appraiser" in Edo's sword market. Sword dealers increased product value by attaching Yamada family certificates, and samurai and daimyo families made it customary to commission the Yamada family before purchase.

In particular, the seventh-generation Asaemon (1749–1813) built on the success of the "Kaihō Kenjaku" by vigorously publishing materials documenting smith information, blade price ranges, and regional characteristics. These works were later systematized as "tōken-sho" (books on swords) and continue to be referenced as primary sources in modern sword research.

From the perspective of the sword industry, the Yamada family functioned as a "blade performance certification authority" during the Edo period, their role equivalent to modern NBTHK (Japan Sword and Art Sword Association) certificates. Though employing the primitive method of cutting tests rather than scientific analysis, they anticipated the essential qualities of an evaluation body: objectivity, systematization, and documentation.

Abolition and Beyond—Wazamono Ranking Culture After Meiji

With the criminal law reforms of Meiji 2 (1869), test-cutting using corpses was abolished. The Yamada family's official duty ended under the eighth-generation Asaemon Yoshitoyoshi, and this unique occupational culture disappeared institutionally.

Yet the influence of the wazamono ranking did not fade; through reprints and citations of sword literature after Meiji, the ranking concepts of "zamono" and "ōzamono" endured. Even in modern sword appraisal, the framework of the wazamono ranking is sometimes referenced as an evaluation standard for late-Edo smiths.

The figure of Yamada Asaemon represents a rare case in sword history, reflecting both the distinctively Japanese spirit of classification evident in the systematic recording and evaluation of a single criterion—blade cutting ability—and the intellectual sophistication of Edo society in layering economic and cultural value upon the sword as a weapon. While his legacy and its ethical dimensions cannot be separated in assessment, the influence the wazamono ranking exerted on the market value system of the katana remains an undeniable legacy in the modern era.