Kogarasu-maru

## Legend and Anecdotes The legend of the bestowal of Kogarasu-maru is the oldest "origin myth" attributed to the Japanese sword. According to tradition, during the reign of Emperor Kanmu (781–806), a great crow—namely the sacred yatagarasu, the messenger of Ise Grand Shrine—appeared. The yatagarasu is a sacred bird with three legs, known in Japanese mythology as the divine bird that guided the eastward campaign of the first emperor, Jinmu. This sacred crow presented a single tachi to the emperor and departed, leaving the blade behind. Emperor Kanmu named this tachi "Kogarasu-maru" ("Little Crow Circle"), saying "I shall call it thus because the crow brought it"—this is said to be the origin of Kogarasu-maru. Thereafter, this tachi became a treasure blade of the imperial court and was passed down to the Kanmu Taira clan (House of Taira), descendants of Emperor Kanmu. The historical significance of this tradition is immense. Taira no Sadamori was a meritorious official who suppressed the rebellion of Taira no Masakado (935–940) and was the figure who formed the core of the Kanmu Taira line. The narrative of guarding the nation with a blade bestowed by the divine served to mythologically underpin the legitimacy of the House of Taira as a warrior clan. The fact that Kogarasu-maru was held as a precious treasure of the House of Taira suggests it constituted part of the Taira clan's power base. The structure of the double-edged-point construction (hone ryouha-zukuri), with extremely few comparable examples elsewhere, would have imparted a profound sense of otherworldliness to anyone who actually held this blade. Because the point is double-edged, it possesses a distinctive weight balance unlike ordinary tachi, offering versatility suited to both thrusting and cutting. There is debate as to whether this structure was influenced by continental straight swords or arose uniquely in Japan; in either case, there is no dispute that it is an invaluably precious artifact filling the "missing link" in the developmental history of the Japanese sword. After the House of Taira's demise in the Battle of Dannoura (1185), the details of how Kogarasu-maru was transmitted remain unclear. One account suggests it was secretly retained by remnants of the Taira clan; another claims it was returned to the imperial court. What is certain is that this blade ultimately passed to the imperial house and endures as an imperial treasure (gomotsu) to this day. This blade, surviving more than twelve centuries, is a unique being that conveys the "beginning" of Japanese sword culture to the present and occupies the position of "ancestor" to all Japanese swords.