Yongwang the dragon king
At a Glance
- Central figures: Yongwang, the Dragon King of the East Sea (Donghae); King Munmu, the thirtieth king of Silla, who unified the three kingdoms and asked to become a sea dragon after death; Munmu’s son King Sinmun.
- Setting: The kingdom of Silla on the Korean peninsula, seventh century; the East Sea coast near the burial rock of Daewangam and the underwater tomb of Munmu.
- The turn: Munmu, dying, commands that his body be cremated and his ashes scattered over the East Sea so that he may become a dragon and protect Silla from Japanese pirates.
- The outcome: After Munmu’s death and sea burial, a great dragon is seen in the waters near the rock; his son Sinmun later receives a bamboo flute from the dragon’s island that, when played, calms storms and repels invaders.
- The legacy: The rock of Daewangam off the coast of Gyeongju remains a site of remembrance, and the bamboo flute Manpasikjeok - “the flute that calms ten thousand waves” - became one of the great treasures of the Silla court.
Munmu had spent thirty years at war. He had taken Baekje. He had taken Goguryeo. He had driven Tang China’s armies back across the Yalu when they tried to keep what they had helped him conquer. By the time the peninsula was his - one kingdom, Silla, from the southern coast to the old Goguryeo lands - his body was failing him.
He called his ministers to his chamber at Gyeongju and told them what he wanted. Not a royal tomb. Not a stone mound in the hills with jade and gold horse-trappings. He wanted fire, and then the sea.
The Dying Command
The ministers did not argue. Some may have wanted to - Silla kings were buried in great mounds with crowns of beaten gold, with glass beads from as far as Persia, with clay figures of servants and horses. But Munmu had unified three kingdoms. He had earned the right to choose.
He said: burn my body according to Buddhist rites. Take the bones that remain. Scatter them in the East Sea, over the rock that faces Japan. I will become a dragon. I will guard the waters.
His son, the crown prince who would become King Sinmun, knelt and received these instructions. The year was 681 by later reckoning.
Munmu died. They cremated him. A procession carried what remained to the coast east of Gyeongju, where a flat rock sat just offshore, visible at low tide, submerged at high. They placed the ashes in the water above the rock.
The sea accepted them.
The Rock in the Water
The rock became known as Daewangam - “Great King’s Rock.” Fishermen who passed it in their boats said the water around it moved strangely, even on calm days. There were currents where no current should be. Sometimes, at dawn, they saw something long and dark beneath the surface - a shape too large to be a fish, too purposeful to be kelp.
Sinmun became king. The Japanese pirates who had raided Silla’s coast for generations did not stop coming, but their raids grew less successful. Ships foundered on clear days. Storms rose from nowhere and scattered fleets that had been sailing in formation. The fishermen along the coast said Munmu was keeping his promise.
Whether Sinmun believed them is not recorded. What is recorded is that in the second year of his reign, a minister came to him and said that a small island had appeared in the East Sea - or rather, that an island that had always been there now had something on it. A stalk of bamboo had grown overnight, impossibly tall, and it split into two during the day and merged into one at night.
The Island and the Bamboo
Sinmun sailed out to see it. The bamboo stood on the island’s only hill, thick as a man’s arm, and when the wind blew through it the sound carried across the water like a voice that could not quite form words.
A dragon rose from the sea beside the island. It was enormous - the accounts say its body was dark as iron, its eyes the color of deep water. It spoke to Sinmun. Some versions say it was Munmu himself; others say it was Yongwang, the Dragon King of the East Sea, who had received Munmu’s spirit into his underwater kingdom and now acted as intermediary.
The dragon told Sinmun to cut the bamboo and make a flute from it. The bamboo that splits and rejoins - two becoming one, one becoming two - holds the principle of the world’s balance. A flute made from it will calm any storm, repel any army, end any drought, and still any plague.
Sinmun cut the bamboo. His craftsmen fashioned a flute. They called it Manpasikjeok - “the flute that calms ten thousand waves.”
The Flute Played
The Samguk Yusa records what happened when Sinmun played it. Enemy soldiers who had been massing at the border retreated. A storm that had been destroying the southern harvest broke apart. The sea, which had been rough for weeks, went flat and silver.
Sinmun kept the flute in the treasury at Wolseong Palace in Gyeongju. It was not played lightly. It was brought out when invasion threatened, when the rains failed, when sickness moved through the capital. Each time, the playing worked.
Whether the flute survived the fall of Silla centuries later is unknown. The Samguk Yusa, compiled by the monk Iryeon in 1281, treats its existence as historical fact - an artifact of state, not a legend. It records the specific dates, the specific island, the specific officials who accompanied Sinmun.
Yongwang’s Domain
Yongwang - the Dragon King - was not only Munmu’s posthumous patron. In Korean tradition, the Dragon King rules the underwater palace beneath the East Sea, a court as elaborate as any on land, with ministers and soldiers and treasuries of coral and pearl. Fishermen made offerings to him before every voyage. Coastal villages held rites at the water’s edge, burning paper and pouring rice wine into the surf, asking Yongwang to hold back the storms and send the fish close to shore.
He appears throughout Korean folklore as a figure of immense power and limited patience. In the tale of the Byeoljubu - the story of the rabbit and the turtle - it is Yongwang who sends the turtle to the surface to fetch a rabbit’s liver, the only cure for his illness. The turtle tricks the rabbit into riding on its back to the sea palace. The rabbit, facing death, tricks the dragon king back, claiming it left its liver on the shore. Yongwang, furious but outwitted, lets the rabbit go.
He could be generous. He could be deadly. He governed the waters the way a king governed a kingdom - with authority that did not need to explain itself.
The Rock at Gyeongju
Daewangam still sits in the water off the coast near Gyeongju. Tourists visit it now. The sea around it is shallow enough that the rock’s flat back shows at low tide, dark and squared off, almost architectural, as if someone had placed it there on purpose.
The fishermen of that coast no longer make the old offerings. But the rock remains where Munmu asked to be placed, facing east across the water toward the direction the pirates came from, in the sea he said he would guard.