Âu Cơ (chữ Hán: 甌姬; IPA: [əu˧ kəː˧]) was, according to the creation myth of the Vietnamese people, an immortal mountain snow goddess who married Lạc Long Quân (lit.

'Dragon Lord of Lạc'), and bore an egg sac that hatched a hundred children known collectively as Bách Việt, ancestors to the Vietnamese people.

When Âu Cơ stopped flying to see the very person that saved her, she turned back into a tiên (immortal) and instantly fell in love with her savior.

However, despite their love for each other, Âu Cơ had always desired to be in the mountains again and Lạc Long Quân, too, yearned for the sea where the length of days are measured by seasons.

[8] Ngô Sĩ Liên commented in the sử ký on the somewhat primitive nature of the relationship between the two progenitors, given that Lạc's father Kinh Dương Vương and Âu's grandfather Đế Nghi were brothers.