Ryūjin or Ryōjin (龍神), which in some traditions is equivalent to Ōwatatsumi, was the tutelary deity of the sea in Japanese mythology. This Japanese dragon symbolized the power of the ocean, had a large mouth and was capable of taking human form. Ryūjin lived in Ryūgū-jō, his palace under the sea built of red and white coral, from where he controlled the tides with magical tidal jewels. Sea turtles and jellyfish are often represented as his servants.
Ryūjin was the father of the beautiful goddess Otohime, who married the hunter prince Hoori. The first emperor of Japan, Emperor Jimmu, is said to have been the grandson of Otohime and Hoori. Therefore, Ryūjin is said to be one of the ancestors of the Japanese imperial dynasty.
Alternative Legends[]
According to legend, Empress Jingū was able to perform her attack on Korea with the help of Ryūjin's tidal jewels. Confronting the Korean army, Jingu threw the kanju (干 珠 "tidal ebbing jewel") into the sea and the tide receded. The Korean navy grounded and the men got out of their ships. Then Jingu threw the manju (満 珠 "tidal current jewel") and the water rose, drowning the Korean soldiers. The Gion Matsuri festival is held at Yasaka Shrine to celebrate this legend.
Another legend involving Ryūjin is the story about how the jellyfish lost their bones. According to the story, Ryūjin wanted to eat monkey liver (in some versions, to cure an incurable rash) and sent the jellyfish to get him a monkey. The monkey managed to run away from the jellyfish by telling them that he had put his liver in a jar in the forest, offering to go and get it. When the jellyfish came back and told Ryūjin what happened, Ryūjin got so angry that he beat the jellyfish until their bones were pulverized.
In Shintoism[]
Ryūjin shinkō (竜 神 信仰 "dragon of good faith") is a form of Shinto religious belief that reveres dragons as water kami. It is connected with agricultural rituals, rain prayers and the success of fishermen.