Ōnin War

The Ōnin War (1467–1477) turned Kyoto into a battlefield for eleven years, destroying much of the capital and fracturing the Muromachi shogunate beyond repair. Its consequences for Japanese sword culture were profound and lasting.

The war began as a dispute over the succession of the eighth Ashikaga shogun, with the Hosokawa clan leading the Eastern Army and the Yamana clan commanding the Western Army. But the deeper cause was the breakdown of the shogunal system that had maintained order since the fourteenth century.

For sword culture, the most immediate impact was a massive surge in demand. Ashigaru — foot soldiers drawn from the lower classes — were mobilized in unprecedented numbers, requiring affordable, practical blades rather than the aristocratic tachi swords of earlier eras. The uchigatana, worn edge-up at the hip rather than suspended edge-down, became the dominant style. Osafune in Bizen Province responded with industrial-scale production of practical blades known as kazu-uchi-mono (mass-produced swords), establishing the Late Bizen tradition that would supply armies throughout the Sengoku period.

The war also scattered Kyoto's refined swordsmiths. The Awataguchi and other Yamashiro-tradition schools, which had produced Japan's finest court blades, dispersed to the provinces, spreading their techniques while losing the concentrated expertise that made their finest work possible. Meanwhile, Mino Province's pragmatic smiths rose to prominence, their broad-tipped, practical blades perfectly suited to the new warfare.

Paradoxically, the war that created demand for mass-produced swords also intensified the culture of connoisseurship. As Shogun Yoshimasa retreated from politics to his elegant Higashiyama villa — later the Silver Pavilion — he and his circle developed the aesthetic refinements of higashiyama bunka, including systematic sword appreciation. The chaos of war and the refinement of art grew from the same soil.