Ōnin War

The Ōnin War (1467–1477) was a great upheaval that hollowed out the Muromachi shogunate and pulled Japan into roughly a century of the Sengoku (Warring States) period. Its origins lay in the succession question within the shogunal house and in power struggles among the shugo daimyō. The influence this eleven-year conflict had on sword culture, however, was immeasurably great.

Background to the War: The Succession Dispute in the Shogunal House

The eighth shogun, Ashikaga Yoshimasa, had long had no heir and had named his younger brother Yoshimi as his successor. However, when Yoshimasa's wife, Hino Tomiko, bore a son (later Yoshihisa), the succession question of the shogunal house became complicated. Power struggles among the shugo daimyō became entangled with it. Kanrei (shogunal deputy) Hosokawa Katsumoto and the powerful western leader Yamana Sōzen (Mochitoyo) became the axis of the conflict, and they clashed in Kyoto in Ōnin 1 (1467).

Kyoto Becomes a Battlefield and Sword Demand Explodes

The urban fighting centered on Kyoto brought unprecedented demand for swords to Japan's sword culture. In this war, large numbers of lower-ranking foot soldiers called ashigaru were mobilized, and the main weapon shifted from the naginata, suited to individual combat, to the yari (spear), suited to group fighting. The move from one-on-one combat to group tactics advanced rapidly.

Meeting this demand was the sword-producing region clustered around Osafune in Bizen Province (present-day southeastern Okayama Prefecture). Known as "Bizen Osafune," this region shifted to a mass-production system after the Ōnin War. Smiths of the Osafune school produced large quantities of practical mass-produced blades called kazu-uchi-mono and supplied them to military commanders, ashigaru, and rural warriors across the country. Blades of this period, generally called Sue-Bizen, fell short of the masterpieces of the Kamakura and Nanbokuchō periods in refinement. In practical usability and volume of circulation, however, they were unmatched by any other producer.

The Ruin of Kyoto and the Rise of Mino Swordsmiths

The ruin of Kyoto also dealt a heavy blow to the Yamashiro-school smiths, who were tied to court culture.

Meanwhile, smiths of Mino Province (present-day Gifu Prefecture) rose rapidly in the wake of the Ōnin War. The Mino tradition (Mino-den) is characterized by practical construction that resists breaking, which suited the battlefields of an age of disorder. Seki in Mino (present-day Seki, Gifu Prefecture) flourished as a sword-producing center. Together with Bizen Osafune, it became one of the two great centers of Japanese swordmaking in the Sengoku period after the Ōnin War. This rise of the Mino smiths was precisely the structural change in the sword industry that the Ōnin War gave birth to.

Mass Production of Inferior Swords and Cultural Problems

The sharp rise in demand inevitably brought a decline in quality. Swords mass-produced after the Ōnin War varied in workmanship, and later connoisseurs graded them as sue-kotō and kazu-uchi-mono. Between the works of the celebrated Kamakura-period smiths Masamune and Yukimitsu and the mass-produced blades of the Sengoku period, there was a large gap in both technique and aesthetics.

But this era holds a notable paradox. Because demand for swords soared explosively, skilled smiths also gained more opportunities to hone their craft. A market principle began to take hold: "good work sells." This created a competitive environment in which capable smiths could win more orders. It can be said that this competition supported the later development of sword technology in the Sengoku period.

Higashiyama Culture After the War

After the war ended, Ashikaga Yoshimasa built a villa in Higashiyama (present-day Sakyō Ward, Kyoto), later Ginkaku-ji (the Silver Pavilion), and nurtured a refined culture known as Higashiyama culture. Ironically, the Ōnin War, which reduced the capital to ruins, also became the occasion for the ultimate form of beauty: the Higashiyama culture that blossomed on those ruins. Noh, the tea ceremony, flower arranging, and shoin-zukuri architecture were all refined in this period.

The Ōnin War is remembered as the event that "opened the door" to the Sengoku period. In sword history, however, it was a turning point that brought about a transformation: the formation of production centers and the establishment of a mass-production system.