Ittō - ryū ( '' one - sword school '' ) is the ancestor school of several Japanese koryu kenjutsu styles , including Ono - ha , Mizoguchi - ha , Nakanishi - ha , Kogen , Hokushin , and Itto Shoden .
Ittō - ryū ( '' one sword school '' ) is the ancestor school of several Japanese koryu kenjutsu styles . 
 These include Ono - ha , Mizoguchi - ha , Nakanishi - ha , Kogen , Hokushin , and Itto Shoden .