Segata Sanshiro (せがた三四郎 Segata Sanshirō ) is a fictional character created by Sega to advertise the Sega Saturn in Japan between 1997 and 1998. He is a parody of Sugata Sanshirō, a legendary judo fighter from an Akira Kurosawa film.
Sanshiro is a dan holder for multiple Japanese martial arts (karate and iaidou first dan, judo third dan, battoudou fourth dan, toudou 7th dan etc..). He is portrayed by actor Hiroshi Fujioka, who, until that point, was best known for playing the hero Takeshi Hongo in the influential tokusatsu superhero series Kamen Rider.
Sanshiro is a Judo master that tracks down and punishes those who do not play the Sega Saturn. His name sounds similar to the phrase "You must play the Sega Saturn!" (セガサターン、シロ! Sega Satān, shiro! ) as well as "Sega Saturn, White" (セガサターン、白 Sega Satān, Shiro ), a reference to the new white color version of the Japanese Sega Saturn which followed the original gray version.
Sanshiro lives as a hermit high on a mountain, devoting his life to intensive Sega Saturn training. He trains physically every day by carrying around a giant Sega Saturn on his back and punching buttons on its giant controller, as well as mentally by breaking stacks of blocks with his head. His intense training has resulted in his ability to make people explode twice by throwing them, which he does with ease. He also frequently visits the city to seek out people who are not playing the Sega Saturn, and harshly teaches them a lesson. Sanshiro is a serious man with a firm sense of duty, who believes that playing video games is one of the most treasured activities in life.
The character became very well known in Japan, and helped make the Saturn successful in that country. When the CD music single was released, it sold more than 100,000 copies.
When the Saturn was phased out and the Sega Dreamcast released, Sanshiro's end came in the form of a commercial involving a missile directed at the Tokyo headquarters of SEGA, implied to be launched by Sony and Nintendo. Sanshiro heroically jumps off the roof of the building, onto the missile, deflecting it into the atmosphere while riding it, in which he lives his last few moments chanting out "Sega Saturn Shiro!!" for one last time, and is killed in the subsequent explosion. The voiceover narrates that "Segata Sanshiro will live on in your hearts," followed by a display of the game Segata Sanshirō Shinken Yūgi, a Sega Saturn game in which Sanshiro plays a major role.
Segata Sanshiro was present at the launch of the Dreamcast in Japan.
Virtual appearances 
Sanshiro is referenced in the Japanese version of Virtua Fighter 4, in which one of the AI profiles for Akira Yuki is named Segata. This same profile name appears in the US version of Virtua Fighter 4 Evolution.
Sanshiro is seen in Sonic & All-Stars Racing Transformed, riding the rocket from the commercial and carrying a giant Sega Saturn on his back. This, however, only occurs if the player is in the lead at the final lap of Race of Ages.
Critical reception 
The Segata Sanshiro campaign is often cited as one of the major reasons for the success of the Sega Saturn in Japan. Nintendo Power journalist Steve Thomason singled out Sanshiro as the character he would most like to control in the Nintendo DSi game Photo Dojo. Thomason amended that "it's just a shame his greatest skill – throwing opponents to make them explode – couldn't be translated to the game."