Bizen Tradition — The Greatest Sword-Making Province of Japan

The Bizen tradition (Bizen-den) is the largest sword-producing region among the Five Major Traditions of the Japanese sword (Yamato, Yamashiro, Sōshū, Bizen, and Mino), and possesses a continuous history of sword production spanning approximately 600 years from the late Heian period (late 10th century) through the late Muromachi period (mid-16th century), based on the iron and water resources of the Yoshii River watershed in what is now southeastern Okayama Prefecture. In the number of smiths, the quantity of masterworks, and the diversity of schools, Bizen Province surpasses all other producing regions; it is scarcely an overstatement to call it a microcosm of Japanese sword history itself.

The defining characteristics of the Bizen tradition are the chōji-midare hamon and the utsuri. The chōji midare is a repeating pattern of curved hamon resembling carnation blossoms, produced as a result of highly advanced technique achieved through precise control of quench temperature, timing, and clay application. The chōji of the Ichimonji school is particularly bold and powerful; the chōji of the Osafune school is orderly and possesses refinement; even within the shared vocabulary of chōji, the individual character of each school stands out distinctly. The utsuri is a misty white shadow appearing within the blade body, a phenomenon arising from surface-treatment techniques particular to the Bizen tradition, and the utsuri appearing within the fine-flowing itame grain is considered an important point of appreciation.

Bizen smithing lineages can be broadly divided into four periods: ① Ko-Bizen (ancient Bizen), the early Bizen smiths prior to Nagamitsu from the late Heian through early Kamakura period, in which Tomonari and others are remembered as "creators of the Japanese sword"; ② the Ichimonji school, which reached its zenith in the early to mid-Kamakura period, with the Fukuoka Ichimonji (Yoshifusa, Sukemune, and others) and the Yoshioka Ichimonji mass-producing splendid tachi that occupied the highest position as presentation swords to the imperial court; ③ the Osafune school, founded by Mitsutada of the mid-Kamakura period, with Nagamitsu, Kagemitsu, Kanemitsu, Nagayoshi, and Motoshige continuously active throughout the late Kamakura, Nanbokucho, and Muromachi periods; and ④ Sue-Bizen (late Bizen), which undertook mass production in the late Muromachi through Sengoku period, with Sukesada, Kiyomitsu, and others supplying practical combat blades throughout the nation.

Behind Bizen becoming Japan's largest sword-producing region lay the particular geographic and industrial conditions. The sand iron (satetsu) of the upper Yoshii River region (present-day Maniwa and Niimi) was of high quality and produced large quantities of tamahagane suitable for tatara ironmaking. The place name "Nagafune" was formed along the Yoshii River at Nagafune Town (present-day Nagafune, Bizen City), and the coordination of forge work utilizing the water power of the river with the distribution of finished products through water transport formed Japan's largest sword-industry cluster. At the height of the Kamakura period, it is estimated that several dozen smithing workshops were simultaneously operating throughout the Nagafune area, and its production volume far exceeded that of other producing regions.

Statistics on National Treasures and Important Cultural Properties also clearly demonstrate Bizen's prominence. Among the surviving National Treasures of Japanese swords (approximately 122 blades), Bizen pieces constitute the largest proportion, and most of the masterworks housed in the Tokyo National Museum, Kyoto National Museum, the Shōsō-in, and shrines and temples throughout the country are works of the Bizen tradition. The celebrated "Honekui Tōshirō" is a work by the Yamashiro craftsman Awataguchi Yoshimitsu and is counted among the "Three Great Swords Under Heaven"; the "Daitentai Mitsuyoshi" of the "Five Great Swords Under Heaven" is a work by the Chikugo craftsman Mikage Dentai Mitsuyoshi and is not a Bizen piece. The Bizen tradition, both in quantity and quality, continues to exercise an overwhelming presence befitting the "core" of the Five Major Traditions of Japanese swords.