This movie is based on the manga comics by Sanpei Shirato. This manga writer was interested in labour rights and discrimination so these themes may be underlying this script.
The story takes place during the rule of the fourth Shogun of the Tokugawa dynasty, Ietsuna, between the years 1651 and 1680.
The actress Koyuki who plays the Kunoichi (female ninja) Sugaru, and is Kamui's mother-in-law in the story, is actually the wife and mother of her three children of the actor Ken'ichi Matsuyama who plays Kamui.