As with so many other Japanese directors, Masaki Kobayashi used the jidai-geki genre and its focus upon the past to comment on the present. After his three-part WWII epic The Human Condition, Kobayashi went even further back in time to the beginning of the Edo period, after the Tokugawa shogunate had fully consolidated power and settled in to its two-century reign. The director specifically hones in on this precise moment of dawning peace, when the reduction of daimyo resulted in samurai suddenly becoming masterless ronin in a society that had no need for additional warriors. This reduced much of the nobility to conditions of extreme poverty even as it demanded their continued fealty to the feudal order and codes of honor.
One of those codes was the ritual suicide from which the film takes its title. Harakiri is structured around the build-up to an expected act of seppuku, and it shows a particularly gruesome example of one during that escalation. Even today, we consider dying for one's cause an act of extreme nobility and resolve. For Kobayashi, however, it is merely the most repellent example of how the rules of a strictly hierarchical society efface humanity and suppress the will of the individual. The end result rates with the most biting of Mizoguchi's period pictures as Japanese cultural criticism.
