The Buyeonarration in Overlooked Historical Records of the Three Korean Kingdomsis concerned with the identification of ethnic origin in the twelfth-and thirteenth-century Goryeo Dynasty.Before the fifth century，Chinese documents compiled between the Han and the Song dynasties had a clear and consistent record of the legend of Buyeo'sancestors.During the fifth century，this legend began to change，which was then adopted in official historiography in the Northern Dynasty.Later on，it as much laid the narrative foundation for the successive Sui and Tang dynasties as became the basis for the historic identity of the Goryeo Dynasty.The reason for such change during the fifth century was the collapse of the Eastern Buyeoand the Nong'an Buyeo .As this legend played a role of legitimating political rule and mass mobilisation in Northeastern China and the Korean Peninsula，other ethnic groups utilised this legend as a politico-historic capital to build their own historic origin and identity，thus enabling this legend to retain its presence through changed forms.When the Goryeo Dynasty began its reconstruction of historical narration，this legend was used again as an important historic capital integrated into the history of the Korean Peninsula.Through the narration in Overlooked Historical Records of the Three Korean Kingdoms，this legend has come to shape the conceptions of history in modern South Korea.