During the climactic sea Battle of Dan-no-ura in April 1185, Antoku's grandmother Taira no Tokiko took him and plunged with him into the water in the Shimonoseki Straits, drowning the child emperor rather than allowing him to be captured by the opposing forces.

Antoku's tomb is said to be located in a number of places around western Japan, including the island of Iwo Jima, a result of the spreading of legends about the emperor and the battle.

Naturally, he held no actual power, but rather his grandfather Taira no Kiyomori ruled in his name, though not officially, as sesshō (regent).

In 1183, when Minamoto no Yoshinaka entered the capital, the Taira clan fled with the young emperor and the sacred treasures to Yashima (the name of a place inside modern-day Takamatsu, Kagawa).

[9] Kugyō (公卿) is a collective term for the very few most powerful men attached to the court of the Emperor of Japan in pre-Meiji eras.

During Antoku's reign, this apex of the Daijō-kan included: After his drowning, in order to mourn the body and placate any restless spirits, the Amidaji Goeidō was built.

The Imperial Household Agency designates Amida-ji no misasagi (阿彌陀寺陵) near Akama Shrine in Shimonoseki as Antoku's tomb.