In the Hùng Dynasty, there was an orphan, Mai An Tiêm. He was hardworking and wise and helped an old couple living with him to survive.
King Hùng decided to adopt this child because of the orphan's warm heart. Mai An Tiêm grew up as a strong and brave man, who proved himself worthy and loyal to the king.
During a feast with all the princes, Mai An Tiêm was telling his friends on how grateful he was toward the king and stayed humble. The King's real son jealous of Mai An Tiêm told the King on how ungrateful Mai An Tiêm was and saying he was arrogant, disrespectful, and ambitious. the king was infuriated he decided to take Mai An Tiêm and his family to an island only leaving them with an old blade and a couple of seeds.
Mai An Tiêm and his family made a stable life there growing vegetables and fruit and creating clothes with animal skins.One day Mai An Tiêm saw crows dropping black seed he decided to grow the seeds and see what it will become.
The seeds had turned into vines with a strange round fruit with it. The fruit was juicy and sweet. He named it dưa hấu since it tasted like a melon. Mai An Tiêm decided to carve his name in the fruit and threw it in the ocean. Once more people found out about the fruit soon Mai An Tiêm had many ships to buy the exotic fruit.
The watermelon was served to the king. He enjoyed the watermelon very much. When he asked about the fruit he found out Mai An Tiêm was the one who grew them. The king decided to bring Mai An Tiêm back for his loyalty towards the King.