Thousands of years ago, Kinh Duong Vuong, King of Xich quy, married Long Nu, a princess from Dong Dinh Ho.  Because of Long Nu's origin, their son Sung Lam, populary known as Lac Long Quan, was believed to be descended from the line of the Dragons.  Lac Long Quan had superhuman strength, and he liked to stay near the water.  He succeeded to the throne of his father and governed the Lac Viet tribe.

During that time, the Lac Viet tribe was still isolated.   Monsters and demons often appeared to harass people.  There was a giant fish called Ngu Tinh, who lived hundreds of years in the East Sea.  Ngu Tinh always swallowed up big fishing boats when they passed by his gulf.  Thus, the fishermen were very frightened of him.

Lac Long Quan heard about Ngu Tinh's evil deeds and decided to exterminated him.  He commanded his tribesmen to make a huge boat and went looking for Ngu Tinh.  When he saw Ngu Tinh, he launched the sharp trident into the giant fish's mouth.  This put Ngu Tinh in great pain.  He soon died, floundered about the water.  Lac Long Quan cut off Ngu Tinh's head with his sword.  Thus, he had terminated the oppressing force for all the people in the Coast.

There was another evil oppression at Long Bien Province.   The children there were often being taken away by Ho Tinh, an wily old fox with nine tails.  Ho Tinh lived in a deep cave and usually got out at nights to kill children.  Lac Long Quan weaved five colors threads into a big lasso and set up a trap at the entrance to the cave.  When Ho Tinh got out that night, he was trapped; his neck was stuck in the lasso and he died.

On the way to the highlands of Phong Chau, Lac Long Quan was told about the evil stories of Moc Tinh.  Moc Tinh was a century old tree demon.   He usually transformed into a human form and went to sabotage the villager's farms at nights.  Lac Long Quan asked his men to make a big axe.  He cut that tree down and Moc Tinh died within the tree.

After completely destroying the tree demons, Lac Long Quan educated his trebespeople about agriculture : how to sow rice seeds and harvest rice.   Rice can be cooked by putting in a bamboo tube with some water and broil over the fire.  One then splits the bamboo tube to get cooked rice.

Fishing boat usually had two big eyes painted on both sides of the anterior end.  Fishermen had tattoos with designs of ferocious animals.   Lac Long Quan believed that it was beneficial to have tattoo when the fishermen dive into the water, they would scare off the other marine animals with their mimicking designs.

At that time, De Lai, King of another northern tribe made a trip to South.  He liked Lac Long Quan very much and married his daughter Au Co to Lac Long Quan.  The bride groom was a talented man, the bride was a beautiful lady.   They were a well assorted couple.  The people in the tribe were very happy.   They feasted for months.

Au Co got pregnant after one year.  The tribespeople gathered up to help Au Co prepare for birth : some boiled water, others sewed clothes or diapers.  But Au Co only gave girth to a big membranous sac instead of a baby.

The sac then became bigger and bigger.  On the seventh day, it suddenly busted:inside there were one hundred eggs.  Each egg hatched into a little boy.  The boys stood up and ran to their mother.