This much we know, but who was his mother? Well local historians claim his mother is none other than Ngoc Luong Than Long Hong Dang Ngan, wife of King Duong Vuong (the nation's founding father), mother of Lac Long Quan and grandmother of the first Hung king. In short, she was the first lady of Vietnam.
The anniversary of her death was commemorated earlier this month.
Falling on the 10th day of the 10th Lunar month, the anniversary of Queen Than Long's death is celebrated by a myriad of people in northern Vietnam. It was previously considered a national festival. This year, dozens flocked to Phu Tho province in order to visit Den Tien (fairy temple).
Tien temple was first built by King Kinh Duong Vuong as a present for his wife, Queen Than Long. He originally named it Tien Cat palace (palace of the fairies).
When Queen Than Long passed away, Lac Long Quan changed the name to Den Tien and ordered three of his sons (Cu Tinh Lang, At Tinh Lang and Linh Thong Thuy) and two princesses (Thuy Tinh and Bach Hoa) to guard it.
The temple stood for thousands of years until it was destroyed during warfare in 1949. In the 1960s, the Viet Tri concrete plant was built on the site of the ruins.
Personal crusade
Khanh Hoai has spent the past 30 years researching the history behind Den Tien. As principal of the first secondary school in Viet Tri, he first became interested in the temple after stumbling across some ancient relics in the area.
He has since collected more than 100,000 documents relating to the temple, including a variety of poems, legends and folksongs.
"One of the country's most important temples has disappeared," Hoai said. "And so have the relics. Younger generations may have already forgotten about the sacred place, but the images linger on in the elderly."
Hoai has spent the past few years trying to raise funds to restore the temple to its former glory. Work on developing the new site finally began in 2000, with cultural officials giving their seal of approval in July this year.
Built on 7,000 square metres of land, the new temple looks over the Red River towards Ba Vi mountain in the southwest.
The construction was overseen by Thich Vien Thanh, chief monk of the Perfume Pagoda (Chua Huong).
"People have said the total cost of rebuilding the temple stands at US$448,000-641,000," Hoai said.
Despite the enormous task still in front of him, Hoai hopes that Vietnamese people will visit the temple and pay homage to their country's first lady.
"During the feudal dynasties of Vietnam, kings used to hold ceremonies at Den Tien before going on to the Temple of the Hung Kings," he said. "I hope every tourist visiting the former Van Lang capital will come here first."
Timeout