The four Dragon Kings (龍王; pinyin: Lóng Wáng) are, in Chinese mythology, the divine rulers of the four seas (each sea corresponds to one of the cardinal directions). Although Dragon Kings appear in their true forms as dragons, they have the ability to shapeshift into human form. The Dragon Kings live in crystal palaces, guarded by shrimp soldiers and crab generals.
Besides ruling over the aquatic life, the Dragon Kings also manipulate clouds and rain. When enraged, they can flood cities. According to The Short Stories on the Tang People (唐人傳奇 Tangren Chuanqi), the Qian Tang Dragon King did just that when he found out his niece had been abused by her husband. Qian Tang also ate the abusive husband.
The Dragon King of the Eastern Sea is said to have the largest territory.
Dragon Kings appeared commonly in literature. Detailed descriptions were given of the finery of their crystal palaces. A Dragon King is one of the main characters in the tenth chapter of Journey to the West.
There are numerous temples dedicated to Dragon Kings in China. One temple in Beijing was built during the Yuan Dynasty and renovated in the early 21st century. Ch'ao-t'ien Palace (朝天宮) of Peikang Township (北港鎮), Yunlin, devoted to the goddess Matsu, also has human-shaped statues for the four Dragon Kings, each riding on a dragon. In contrast to the Dragon Kings, Matsu, although also a deity of sea, is a motherly figure who never wreaks havoc.