As in the case of Sasuke, Saizō might be a fictional creation of the Meiji-period popular literature, possibly based on Kirigakure Shikaemon.
According to the historian Stephen Turnbull[1] and non-fiction writer Joel Levy,[2] there is a historical record of a failed assassination attempt by a ninja called Kirigakure Saizō, sent by the warlord Tokugawa Ieyasu to kill his rival Toyotomi Hideyoshi (Tokichiro Kinoshita).
According to another version of this incident, presented by the martial artist and researcher Donn F. Draeger,[3] the "careless ninja" Saizō was captured while only spying on Hideyoshi, which actually saved the life of the warlord because he was about to be killed by a double agent, Yusuke Takiguchi; Saizō's life was then spared on the condition of declaring loyalty to the Toyotomi clan.
The martial artist and author Stephen K. Hayes compared the portrayal of Saizō in the Japanese children books to this of another ninja "romantic figure" of the bandit hero Ishikawa Goemon.
The modern ninja named Saizo are also player characters in the video game series Power Instinct (Saizo Hattori) and Breakers Revenge (Tobikageno Saizō), while the title character in the manga and anime series Igano Kabamaru was raised and trained by his grandfather Saizō Igano.