The design is a traditional one representing a battle scene which took place during the naval battle of the Bay of Katsuura in February, 1185.
At dusk, after a day's battle, a small boat approached Mure beach from the open sea. Hoping to make the Minamoto waste arrows, a samurai from the Taira hoisted a 'war fan' up a pole. The Taira challenged the Genji to shoot down the fan. Nasu Munetaka, a Genji samurai of Nikko and an expert archer, was ordered by his commander, Yoshitsune, to perform this difficult task. The particular importance of this fan is that it bore the Mon of the Taira, and bringing it down would be a serious blow to the honor and morale of that clan. After much trepidation, self doubt, and a prayer to Hachiman, Munetaka took careful aim and brought down the Taira emblem. It is said that both sides cheered at this uncanny marksmanship. This is one of the most celebrated events in Japanese history because the loss of that fan had much to do with the loss of the battle and the downfall of the Taira and the accession of the Minamoto.