Tachi

The tachi is a Japanese curved, single-edged sword that emerged during the Heian period and remained the principal sword form of mounted Japanese warriors through the Kamakura period, roughly the ninth through fourteenth centuries, before the shorter, differently mounted katana gradually became the more common battlefield sword among samurai. Unlike the katana, which was worn edge-up thrust through a belt sash, the tachi was suspended edge-down from cords hung at the waist, a mounting suited to a mounted warrior drawing and cutting downward from horseback rather than the quick edge-up draw the later katana was designed for on foot. Sword scholars and Japanese sword-appraisal tradition treat the tachi as the direct structural and stylistic ancestor of the katana, and many surviving tachi blades were later shortened and remounted as katana as Japanese fighting styles and fashions shifted toward infantry combat in subsequent centuries.