The 1580 was one of many battles fought between the Hà Âjà  and Takeda clans during Japan's Sengoku period. It is distinguished, however, as one of the very few naval battles to be fought in pre-modern Japan.
The battle took place off the coast of the Izu peninsula between the navies of Hà Âjà  Ujimasa, the head of the Hà Âjà Â, and those of Takeda Katsuyori, the head of the Takeda.
The Fà «ma ninja led by Fà «ma Kotarà  covertly infiltrated and attacked a camp of the Takeda clan forces at night, succeeding in causing severe chaos in the camp, which resulted in massive casualties among the disoriented enemies as they attacked each other.
Later, while the navies faced off, the land armies of each family advanced towards one another. In the end, the Hà Âjà  were victorious.