It was originally performed as a ritual in order to honor the Kami and provide a healthy harvest. The ring in which the sumo match is held is called a dohyō, which is still considered sacred. The roof over the dohyō is called a yakata, which originally represented the sky as an opposite of the dohyō’s representation of the earth. The gyōji, who are officials who judge each match, wear costumes based upon what was worn during the Heian period of Japan from 794 to 1,185 (David D.). Before the game, the gyōji purify and bless the ring by burying dried squid, kelp, and salt within its center. Sake is partaken and what is left after is poured over the ring’s outer line as a tribute to the Kami. During the Edo period of 1603 to 1868, sumo became a sport conducted at the imperial court instead of a religious ritual:
“Matches were held to raise money to construct shrines and temples or to replace bridges, and the professional sumo wrestler was born. A sport that was once enjoyed only by the rich and powerful became popular among the masses. Sumo events were often held in Edo (now Tokyo), Osaka, and Kyoto, and the sport's popularity grew with the sales of color woodblock prints featuring sumo scenes and pictures of wrestlers. The government of the time, though, disapproved of fighting and often issued orders banning sumo.” (Kids Web