In Japanese beliefs, Hachiman is the syncretic divinity of archery and war, incorporating elements from both Shinto and Buddhism. Although often called the god of war, he is more correctly defined as the tutelary god of warriors. He is also the divine protector of Japan, the Japanese people and the Imperial House, the Minamoto clan and most samurai worshipped him. The name means "God of Eight Banners", referring to the eight heavenly banners that signaled the birth of the divine Emperor Ōjin. His symbolic animal and messenger is the dove. Since ancient times Hachiman was worshiped by peasants as the god of agriculture and by fishermen who hoped he would fill their nets with much fish. In Shinto, he became identified by legend as the Emperor Ōjin, son of Empress Jingū, from the 3rd–4th century.
Because as Emperor Ōjin he was an ancestor of the Minamoto clan, Hachiman became the tutelary kami of the Minamoto samurai clan. Minamoto no Yoshiie, upon coming of age at Iwashimizu Shrine in Kyoto, took the name Hachiman Taro Yoshiie and through his military prowess and virtue as a leader, became regarded and respected as the ideal samurai through the ages. After Minamoto no Yoritomo became shōgun and established the Kamakura shogunate, Hachiman's popularity grew and he became by extension the protector of the warrior class the shōgun had brought to power. For this reason, the shintai of a Hachiman shrine is usually a stirrup or a bow. Throughout the Japanese medieval period, the worship of Hachiman spread throughout Japan among not only samurai, but also the peasantry. So much so was his popularity that presently there are 2500 Shinto shrines in Japan dedicated to Hachiman, the second most numerous after shrines dedicated to Inari. Usa Shrine in Usa, Ōita Prefecture is head shrine of all of these shrines and together with Iwashimizu Hachiman-gū, Hakozaki-gū and Tsurugaoka Hachiman-gū, are noted as the most important of all the shrines dedicated to him. The crest of Hachiman is in the design of a mitsudomoe, a round whirlpool or vortex with three heads swirling right or left. Many samurai clans used this crest as their own, including some that traced their ancestry back to the mortal enemy of the Minamoto, the Taira of the Emperor Kanmuline.