A shrine in Shimonoseki, Yamaguchi which enshrines emperor Antoku (1178-1185) whose sentei-sai or previous-emperor-matsuri instituted by Antoku's successor, Gotoba, takes place on April 23rd-25th. Antoku was emperor from 1180 to 1185 when he drowned near the site of the shrine during the naval battle of Dan-no-ura, in which the Taira were finally defeated by the Minamoto or Genji clan. Antoku was eight when he died and the toys he played with have been preserved at the Itsukushima jinja, the Taira (Heike) family shrine. The Akama jingu was completely destroyed by bombing in the second world war and has been rebuilt with a gate (suitenmon) in the ryugu or 'dragon palace' style, a reference to the watery manner of Antoku's death. (See Ryujin).
A Popular Dictionary of Shinto. Brian Bocking.