According to Legend of Qinghai, a long time ago, the King of Dragons was very happy to see that his queen had given birth to four dragons. Many years later, the four dragons grew up, causing more and more mischievous pranks until the Dragon King was out of breath. One day, the King of Dragons came up with a way to summon all the dragon princes into the Crystal Palace. He said, "You have grown up, so you should all have your own side." Then he ordered the eldest prince Ao Guang to become the King of the East China Sea, the second prince Ao Qin to become the King of the South China Sea, and the third prince Ao Shun to become the King of the North Sea. The King of Dragons wanted to keep the little prince Ao Run beside him, but Ao Run said, "I will be the King of the West Sea!" The King of Dragons laughed and praised him. After the Huaxia Jiuzhou, Ao Run did not see the West Sea. When he came to the southern foot of Qilian Mountain, he was exhausted. He cried sadly, "How can I be the King of the West Sea without the West Sea?" Then he climbed to the top of Qilian Mountain and made a big storm, but it did not suffice. When the Jade Emperor saw this happen, he felt pity. Therefore, he sent Leigong, Dianmu, Fengbo, and Yun Tong to help Ao Run. Lightning, thunder, and storms created Haizi with an average water depth of more than 5,000 square kilometers and a depth of more than 20 meters, which became the West Sea. Since then, Ao Run has become the Dragon King of the West Sea. Ao Run has three children. His sons are Ao Lie, who was the steed of Tang Sanzang, and Ao Moang. He has a daughter named Ao Cinxin, also known as the Xihai Longnü.
In Korean mythology
In the better-known Jakjaegeon myth, a part of the Goryeo Dynastyfounding myth, Jakjaegeon kills an old Gwishin with a bow at the request of the Dragon King of the West Sea, who appears to him in a dream. The Dragon King of the West Sea gives him his daughter in gratitude, and the Dragon King of the West Sea tells Jakjaegeon that his grandson will be king. Jakjaegeon has four sons, of which the eldest is Yong Geon, the father of King Taejo of Goryeo. In Korean history, the Dragon King of the West Sea sent a turtle to King Changsu of Goguryeo in congratulation of his transfer of the capital to Pyongyang.
