Kamiizumi Nobutsuna, (上泉 信綱), born Kamiizumi Ise-no-Kami Fujiwara-no-Hidetsuna, (c.1508 – 1572/1577) was a samurai in Japan's Sengoku period famous for creating the Shinkage-ryū school of combat. He is also well known as Kamiizumi Isenokami (上泉 伊勢守) which was his name as a samurai official (武家官位, Bukekani) for a period of time. Early life Kamiizumi was born as Kamiizumi Hidetsuna in his family castle in Kōzuke Province (modern day Maebashi, Gunma Prefecture). His family were minor landed lords in the service of the Yamanouchi branch of the Uesugi clan. At the time of his birth, Kōzuke Province was being contested by the Uesugi, the Hōjō, and the Takeda clans. His family was originally a branch of the Ōgo clan that moved to nearby Kaigayagō Kamiizumi and took its name for their own. When the main Ōgo clan moved to Musashi Province, the Kamiizumi family took over Ōgo Castle, at the southern foot of Mount Akagi. From the age of 13 or 14, Kamiizumi was tutored by a Zen rōshi named Tenmyō in Zen Buddhism and other Eastern philosophy. In his youth, he went to nearby Shimōsa Province (modern day Chiba Prefecture) and began studying Nen-ryū, and Shintō-ryū. Later he went to Hitachi Province (modern day Ibaraki Prefecture) and studied Kage-ryū. It is not clear who Kamiizumi’s teachers were; in all of his later writings, he marks the start of lineal transmission of his art from himself. He was a younger contemporary of Tsukahara Bokuden. The lineage of Jikishinkage-ryū puts Kamiizumi second after Matsumoto Bizen-no-kami. The lineage of Hikita Kage-ryū puts Kamiizumi second or third after Aisu Ikōsai. In Yagyū Shinkage-ryū, it is believed that Kamiizumi learned Kage-ryū from Ikōsai, receiving full transmission around the age of 23. A few years later, Kamiizumi learned battle strategy and divination from a man named Ogasawara Ujitaka. In the Empi-no-Tachi scrolls that Kamiizumi gave to Yagyū Munetoshi and Marume Nagayoshi, he wrote that he had studied Nen-ryū, Shintō-ryū, Kage-ryū, and others, and had developed an innovation from Kage-ryū, and thus named his school Shinkage-ryū (New Kage-ryū). In his book Shōden Shinkage-ryū, Yagyū Toshinaga surmised that Kamiizumi created Shinkage-ryū in his mid-30s. As a general In 1555, Hōjō Ujiyasu ordered an attack on Ōgo castle, now commanded by Kamiizumi. Kamiizumi surrendered the castle without a fight, and joined Ujiyasu. This same year, Uesugi Kenshin invaded western Kōzuke in order to re-take Hirai Castle. Kamiizumi abandoned the