Kusanagi Sword - Kusanagi Sword

One of the Three Sacred Treasures. When Susanoo-no-Mikoto defeated the Yamata-no-Orochi in Izumo, he obtained this sword from its tail, and it was dedicated to Amaterasu-Omikami. Later, Emperor Keikō's son Yamato Takeru-no-Mikoto received this sword from Princess Yamato of Ise Saigū. When he was tricked by the kuni no miyatsuko in Sagami and suffered a wildfire, he used the sword to cut down the grass, set fire to the enemy, and escaped. In the Nihon Shoki, it is said that because of this, the name of the sword was changed from Ame-no-Murakumo-no-Tsurugi to Kusanagi-no-Tsurugi. Emperor Yamato Takeru left this sword with Miyazuhime in Owari, and was killed by the god of Mount Ibuki. However, there are doubts about the origin of the sword's name in the Nihon Shoki and whether this sword was a sacred treasure throughout its history.

The name of the sword means "Ferocious Snake", which is appropriate for a sword that originated from a giant snake, but the story of cutting grass is merely a popular interpretation of the origin of the name that was invented later. The reason this sword was identified with Ame-no-Murakumo-no-Tsurugi and made into a sacred sword of the Imperial Family is because it has the same legend as the Han Dynasty's treasured sword, Zandaken. In the 7th year of the reign of Emperor Tenji (668), the sword was stolen and was recovered, but in the 15th year of the reign of Emperor Tenmu (686), it was discovered through divination that the Emperor's illness was the result of the curse of the Kusanagi-no-Tsurugi, and it was returned to Atsuta Shrine. This curse is probably proof that the Kusanagi-no-Tsurugi was not a sacred sword of the Imperial Family. It is likely that when the sacred sword of Atsuta Shrine was stolen and kept in the Imperial Court, measures were taken to make it into a sacred sword of the Imperial Family. In the story of Emperor Yamato Takeru, it is thought that he left the sword with Miyazukehime in Owari as an auspicious tale that answers the question of why the imperial family's sacred sword is enshrined at Atsuta Shrine in Owari.

[Yoshii Iwao]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

三種の神器の一つ。素戔嗚尊(すさのおのみこと)が出雲(いずも)で八岐大蛇(やまたのおろち)を退治したとき尾の中から得た剣で、天照大神(あまてらすおおみかみ)に奉献された。のちに景行(けいこう)天皇皇子の日本武尊(やまとたけるのみこと)がこの剣を伊勢(いせ)斎宮の倭姫(やまとひめ)から賜り、相模(さがみ)で国造(くにのみやつこ)にだまされて野火の難にあったとき、この剣で草を薙(な)ぎ、向かい火をつけて難を逃れたという。『日本書紀』では、このために剣名が天叢雲剣(あめのむらくものつるぎ)から草薙剣に変わったという。日本武尊はこの剣を尾張(おわり)の美夜受比売(みやずひめ)のもとにとどめて、伊吹(いぶき)山の神に殺される。だが『日本書紀』の剣名の由来や、この剣が終始神器であったかは、疑問である。

　剣名の意は「獰猛(どうもう)な蛇」で、大蛇より出た剣名には適切だが、草を薙ぐ話はのちにつくられた命名起源の俗解にすぎない。またこの剣を天叢雲剣と同一視して皇室の神剣としたのは、漢の宝剣・斬蛇剣(ざんだけん)と同じ伝承をもっていたためであり、天智(てんじ)天皇7年（668）この剣の盗難があり、このときは取り戻されたが、天武(てんむ)天皇15年（686）卜(うら)によって天皇の病が草薙剣の祟(たた)りとわかると、熱田(あつた)社に返されている。この祟りは、草薙剣が皇室の神剣でなかった証(あかし)であろう。おそらく、熱田社の神剣が盗難後宮中にあったとき、これを皇室の神剣とする処置がとられたのであろう。日本武尊物語で、この剣を日本武尊が尾張の美夜受比売のもとにとどめておいたのは、なぜ皇室の神剣が尾張の熱田社に祭られているのかに答える縁起譚(たん)であったと考えられる。

［吉井　巖］

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