 The "Samguk Sagi" mentions that Usan had been an independent kingdom based on Ulleungdo.Based on the story of Usan, contemporary chroniclers believed Usando to be one and the same island as Ulleungdo.The Taejong-Sillok (태종실록, Annals of King Taejong) recorded that "60 people were living on Yusan-guk-do (우산국 流山國, Yusan-state-island).