Japan Sumo Association

The Japan Sumo Association is the only organization on a national scale in Japan responsible for the professional and commercial operation of sumo wrestling and is affiliated with the Ministry of Education, Culture, Sports, Science and Technology. Sumo, known as Somachi, originated in China during the Han Dynasty, and consists of two Hercules wrestling each other topless. Sumo is categorized into 10 grades according to athletic performance: shounokuchi, shounidan, sansandan, makushita, joryu, maezumi, kojutsu, sekiwake, daikan, and yokozuna. Yokozuna is the highest ranking title for an athlete and is a lifetime honorary title.