Hōzōin In’ei was a martial arts expert and monk at the Kōfuku Temple during the Azuchi-Momoyama period.
In’ei was the head of the Hōzōin, a sub-temple of the Kōfuku Temple in Nara and thus is known as Hōzōin In’ei. He was the founder of the Hōzōin school of spear fighting.
In’ei was born as the second son of Nakamikado Tanenaga, an adherent of the Kōfuku Temple.
From a young age, he acquired an interest in the arts of the sword and spear. Together with Yagyū Muneyoshi, he learned the sword from Kamiizumi Nobutsuna, the founder of the Shinkage school of sword fighting; further, he learned the spear from Ōkashiwade-no-kami Moritada and the military arts of the Tenshin-Shōdenkataori Shintō school from Ōnishi 木春見. In’ei, along with Muneyoshi and Anazawa Morihide, devised fifteen forms (predefined sets of movements) which became the foundation of the Hōzōin school of spear fighting. This school leveraged techniques of the jūmonji (a spear with curved cross-blades) to enable a variety of means to attack and defend. At the time, these were viewed as ground-breaking developments in the art of spear fighting. Disciples included Nakamura Hisamasa, Takata Yoshitsugu (Matabei), and Kani Yoshinaga. Later, Hisamasa performed demonstrations of the art in front of the shōgun, Tokugawa Iemitsu, on three occasions.
In his later years, on the basis that engaging in military affairs is not the true will of monks, Inshun, a monk designated to become the next abbot, prohibited the learning of military arts at the temple and all weapons were given to his leading disciple, Nakamura Hisamasa. On 8/26 of Keichō 12 (1607), In’ei died at the age of eighty-seven.