Osafune Nagamitsu

Nagamitsu was a swordsmith of the Osafune school, which flourished in the late Kamakura period in Bizen Province (present-day Okayama Prefecture), and is transmitted to have been the son of Mitsutada, the founder of the school. Signed works bearing dates are known, beginning with a tachi inscribed in Shōō 2 (1289), and inscribed with era names such as Einin, Shōan, and Kaei, his period of sword production spanning approximately thirty years. While there was formerly a theory that blades signed "Sakon Shōkan Nagamitsu" represented a second generation, in recent times the prevailing view is that these should be considered as one generation, including those signed with the Sakon Shōkan title. Inheriting the brilliant chōji-midare style that his father Mitsutada had perfected, he refined it further and was the central figure who led Osafune to the golden age of Bizen swordcraft.

His style encompassed a broad range. From magnificent and ornate midare blades interspersed with kawazu-ko-chōji and jūka-chōji, to gentle works with shallow saki interspersed with Nagamitsu's distinctive thick, bulging gunome-style chōji, and even suguha-style blades. The jigane features densely packed, refined ko-itame jihada, with the irregular reflections standing out brightly as a major point of appreciation. The kissaki forms a distinctive shape, becoming slightly irregular above the yokote and returning in a small rounded form, and since this characteristic is shared by his pupils as well, it is called the "three-master kissaki."

The most renowned representative work is the National Treasure "Daihanya Nagamitsu" (Tokyo National Museum). A masterpiece on which a brilliant hamon interspersed with jūka-chōji is forged, it was valued at the extraordinary price of 600 kan during the Muromachi period, and the name was given in analogy to the Daihanyakkyō (Great Prajñāpāramitā Sūtra), a scripture comprising 600 fascicles. It is also known for its provenance, passing from Ashikaga Yoshiteru through Miyoshi Chōkei to Oda Nobunaga and Tokugawa Ieyasu. In addition, there is the National Treasure "Tsuda Tōtōmi Nagamitsu" (Tokugawa Art Museum), so named from having been owned by Tsuda Tōtōmi no Kami Shigechika, a senior retainer of Akechi Mitsuhide; and Nagamitsu has a total of 6 National Treasures, 28 Important Cultural Properties, and 36 Important Art Objects designated, making him one of the smiths of the koto period with the most surviving signed works. The abundance of his signed works has been valued as reliable standard pieces for judging the Osafune style in later authentication.

In terms of lineage, he occupies a key position in the legitimate succession of Osafune. His son Kagemitsu succeeded him as the third generation to establish the main line, leading to the subsequent flourishing of the Osafune school. Nagamitsu, Sanechō, and Kagemitsu, all sharing the aforementioned three-master kissaki, are jointly cited as the "Osafune Sansaku" (three masters of Osafune). In the ranking system of the Japanese Swordsmiths' Dictionary, he is placed in the highest category of "Saijō-saku" (supreme works), and combined with his legacy of numerous named, signed masterpieces, Nagamitsu is highly regarded today as a great master who embodies the pinnacle of the Bizen tradition.