The main purpose of this study is that establishing the historical background of the tale on the Yeonolang and Seonyeo. The conclusions are following. At southern area in the Korean Peninsula, it usually happened that the resident had to leave their hometown and find a newly settled area from 2nd to 3rd century, because immigrants who had gotten advanced political experiences and advanced culture took the resident’s hometown. In particular, the situation of Yeongil area was same as that. In addition, due to the development of Silla, Yeongil area was about to merge with Silla. The Yeonolang and Seonyeo symbolize the resident that leaving Yeongil area and could not stand the pressure. The group of Yeonolang focused on the Japanese islands as their newly settled are, because Yeongil residents were connected with Japanese frequently from 2nd to 3rd century. Meanwhile, queen Himiko[卑彌呼] was inducted into king at the end of 2nd century in Japan, so there was a unitary government that governed loosely in west Japan. However, Himiko’s power was limited to west Japan. For that reason, It was possible that the resident who left Korea and crossed into Japan got ruler positions in some area except west Japan, because they got advanced ironware culture and plenty of political experiences. According to situation between Yeongil and Japanese island, Yeonolang’s tale is based on historical facts that the people who left Yeongil in Korea and settled in Japanese island became the ruler. The reasons that the tale is based on king-Adalla era are following. First,that period was the most friendly time between Silla and Wa. Because of that, the period that Yeonolang was inducted into the king in Japanese island was based on king-Adalla era. On the other hand, king-Adalla era was expected an ominous future to king-Adalla and Park’s royal family, because at that time was the very moment that the throne was changed from Park to Seok. Therefore, it can be assumed that the ominous future of king and royal family became the story that the sun and the moon lost sunlight and moonlight. The reasons why Yeongil area was based on the tale are following. Yeongil area was easy to get Japanese island by ocean current and seasonal wind. In addition, Sadosung which was one of the Japanese’ invasion routes was installed during 2nd and 3rd century in Yeongil area and it was easy to get informayion which was related to Japanese island because there were connections between Japanese and Yeongil area.