Mutsu-no-kami Yoshiyuki

Mutsu no Kami Yoshiyuki was a shinshoku swordsmith active around the Genroku era of the middle Edo period. As for his birthplace, tradition holds that it was either Nakamura in Mutsu Province (present-day Sōma City, Fukushima Prefecture) or Sumiyoshi in Settsu Province (present-day Sumiyoshi Ward, Osaka City), and this remains uncertain. He first went to Osaka and became a student of Yamato no Kami Yoshimichi I, a renowned swordsmith of the Mishina school, where he learned to forge blades. He was subsequently invited to the Tosa domain during the Genroku era and became the forging magistrate; because he actively forged blades for domain retainers, he came to be called "Tosa Yoshiyuki" as well. He received the title of Mutsu no Kami as an official court-granted name (jūryō-mei), and tradition holds that in his later years he returned once more to Osaka, where he spent the remainder of his life. By bringing swordsmithing techniques cultivated in Osaka to southern Tosa, he was a swordsmith who left considerable influence on the sword-forging history of Tosa.

In his forging style, in addition to following the tradition of his teacher Yamato no Kami Yoshimichi, he excelled at forging the elegant kobitagata chōji in the manner of Kawachi no Kami Kunisuke, which was fashionable in Osaka at that time. This hamon, which runs in rounded, bumpy undulations like a fist, is Yoshiyuki's most characteristic feature. Besides this, his work also includes composed suguha and, in his early period, works with sudare-ba hamon. After moving to Tosa, he handled many practical blades for the domain and displayed forceful workmanship with gunome chōji featuring ashi. His skill was highly esteemed and he is classified as a swordsmith of superior quality.

It was as the haitō of Sakamoto Ryōma, a shishi of the late Bakumatsu period, that Mutsu no Kami Yoshiyuki became widely known. This blade was originally a family treasure passed down within the Sakamoto family, and tradition holds that in Keiō 2 (1866) Ryōma requested it from his elder brother Gonpei, the family head, and received it. Ryōma treasured this blade and, tradition holds, kept it close at hand at the time of the Ōmiya Incident, when he was assassinated at the Ōmiya in Kyoto in Keiō 3 (1867). After Ryōma's death the blade remained in the Sakamoto family, but a fire in Taishō 2 (1913) deformed the blade, and when it was subsequently repolished (sai-ha), the original form and the cutting wounds from the assassination were lost. Because the repolishing obscured the original hamon, there was scholarly debate continuing into later years as to whether this was indeed Ryōma's actual blade. In Shōwa 6 (1931) it was donated to the Onshi Kyoto Museum (now the Kyoto National Museum) and entered its collection, but in an investigation conducted in Heisei 27 (2015), traces of Yoshiyuki's characteristic kobitagata chōji hamon were confirmed beneath the repolished jigane, and researcher Miyagawa Teiichi conclusively determined that this was indeed the Mutsu no Kami Yoshiyuki that Ryōma carried at the time of the Ōmiya Incident. It remains in the collection of the Kyoto National Museum and is cherished by many as Ryōma's treasured blade and as a representative work of Yoshiyuki connecting Osaka shinshoku to Tosa.