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A 12th century emperor of Japan, also known as Imperial Prince Tokihito. As a result of becoming caught up in the Gempei War, he died in his eighth year at the battle of Dan-no-ura in 1185. Together with his grandmother, Taira no Tokiko, and the Sword of Kusanagi, one of the Japanese Regalia, he sank to the bottom of sea at the Kanmon Straits.
Shinto priests claim that by performing a ritual similar to the rituals used to summon kami spirits into shintai, they are capable of creating sacred replicas of the Regalia, called "katashiro". If one excludes the original Sword of Kusanagi, allegedly enshrined in the Atsuta Shrine, the katashiro of the sword lost at that time is the oldest one.
His death was the source of countless tales and legends. In books such as Heike Monogatari and Gukanshou, this sword was said to have been a treasure of the undersea dragon palace originally, and the Yamata no Orochi was the Dragon God or a member of its family. In order to retrieve the sword stolen by Susanoo, the Orochi reincarnated as Emperor Antoku.
In Heike Monogatari, there was an account that says when he was born, the traditional rites that are supposed to be performed when a princess is born were performed by mistake. This gave rise to many tales based on the theme that Emperor Antoku was actually female.