Ame-no-Murakumo-no-Tsurugi / Kusanagi-no-Tsurugi (天叢雲剣／草薙剣)

On the riverbank of Izumo, when Susanoo split open the tail of the great serpent he had lured into a drunken stupor, a sword seeped forth from within, trailing its own cold light. Some accounts say a celestial haze drifted around the blade; others, that the clouds themselves had taken the shape of an edge. Its name, Ame-no-Murakumo — Heavenly Gathering Clouds — was a memory carved from the moment of its birth. Later, when it proved its power by cutting through fields of grass, it came to be called Kusanagi, the Grass-Cutter.

Susanoo offered this divine sword to Amaterasu of the High Plain of Heaven, and in time it descended to earth when the heavenly grandchild Ninigi made his descent. Of the Three Sacred Treasures, if the mirror embodies wisdom and the jewel embodies compassion, then this sword is the incarnation of severing force — of martial power and decisive will — so theologians of later ages wrote, again and again.

In the reign of Emperor Sujin, a replica of the sword was fashioned. One might say that the moment the original and its double were separated, something already began to go wrong. The original was carried on Yamato Takeru's eastern campaign, and after the hero's death it remained in the land of Owari, eventually becoming the sacred object enshrined at Atsuta. The replica stayed within the imperial palace, and so two swords breathed quietly on in two different places.

In the turmoil of the Jishō-Juei War, the replica sword fell westward with the Taira clan, and was swallowed by the waves at Dan-no-ura. Said to have sunk into the Kanmon Strait together with the child Emperor Antoku, it was never recovered and was lost. The imperial court obtained another sword from the Grand Shrine of Ise and bestowed upon it the name Ame-no-Murakumo-no-Tsurugi — but as to whether that sword was the true divine blade, the records remain silent.

During the upheaval of the Northern and Southern Courts, two rival dynasties each claimed to possess the sacred sword, and each staked its legitimacy on that claim. Whether the sword in one hand was genuine, or whether both were merely copies, the question was left unanswered when peace was finally brokered. The replica sword enshrined today in the imperial palace refuses all direct viewing, as though it would prefer that no one inquire too closely into its origins.

The sacred object at Atsuta, too, has left no record of any eyes that have seen it. Rumors persist even now of a streak of white light crossing the shrine grounds in the dead of night — but whether that is divine radiance, or whether something sunken on the ocean floor is trying to find its way back, no one has ever been able to say.