Shinkage-ryu is one of the most widely used appellations among Japanese martial arts. This particular ryu, created in the Meiji period, was founded by Imaizumi Hachiro (今泉八郎). Imaizumi studied Sekiguchi Shinshin-ryu jujutsu and Kusunoki-ryu kenpo from Imaizumi Ryusetsusai Tomoaki, later taking his teacher's family name. He later studied Tenjin Shinyo-ryu under Iso Mataemon and Araki-ryu Bojutsu and Torite from Taiboku Kuranosuke (大木蔵之進), a vassal from Iyo-Matsuyama province.
In 1883, Imaizumi became a police instructor in Shitaya, Tokyo. He founded the Enbukan dojo. He died in 1906.