Long ago during the Hùng Dynasty, there was once a wise and hard-working orphan named Mai An Tiêm who earned a small living by helping a elderly family nearby. One day in the summer, King Hùng and his royal court rode through Phong Châu and heard great tales about the orphan. He adopted the young boy.
The boy grew up to be a brave and strong man. He even married the king's daughter. One day, he invited the princes to his house for a feast. Each prince shared a story. The young prince was jealous of him so he went to the kingdom and told that Mai hated the king.
The king was furious about it so he told the soldiers to bring him and his family to a deserted island. His family was brought there the next day.
He built a house out of bamboo stalks and used bamboo shoots for food. Four years had passed. His children had all grown up.
One day when Mai An was resting on the hill, he saw a flock of crows dropping black seeds. He picked them up and chose a good spot to plant them. Later on, the whole hill was filled with watermelons. He called it dưa hấu and started selling them when a sailor found them when Mai An put them in the ocean.
Later on, many more people came to try the watermelons. With the merchant's help, he got to send the watermelons to the king. The king loved the fruit and when he found out that Mai An was the giver, he told the soldiers to bring him back home.