In 1416, Kim In-u was appointed "Inspector of the Muleung Region" and sent to "Muleungdo" to bring back to the mainland people living there. However, when he returned in 1417, it was reported that he returned from "Usando," not Muleungdo, suggesting that the people he met on the island referred to their island as Usando instead of Muleungdo. After receiving Kim In-u's report, ministers started referring to the island group as "Usan-Muleung," suggesting that Usan and Muleung were neighboring islands and that Usan was the larger of the two.
In the following 1425 report, Kim In-u is sent back to the region, but instead of being referred to as "Inspector for the Muleung Region," he is referred to as "Inspector of the Usan-Muleung Region."
The report says that people were living on Muleungdo, but was Muleungdo referring to Ulleungdo or to one of its neighboring islands? We cannot be sure, but Kim In-u was referred to as the "Inspector of the Usan-Muleung Region," suggesting that Usan and Muleung are neighboring islands and that Usan is the larger. Also, in 1417, it was reported that Kim In-u returned from Usando with three residents and tribute that included bamboo and other plant and wood products, however, he had been sent to Muleungdo, not Usando. Again, this suggests that Usando and Muleungdo are neighboring islands that are close enough together to cause name confusion.
Source: 『世宗實錄』 卷 二十九, 世宗 七年 八月 甲戌條
August 8, 1425
甲戌以前判長鬐縣事金麟雨 爲于山武陵等處按撫 初江原道平海人金乙之李萬金亐乙金等 曾逃居武陵島 歲丙申 國家遣麟雨 盡行刷還 癸卯 乙之等男婦共二十八名 復逃入本島 今年五月 乙之等七人 留其妻子於本島 乘小船潛到平海郡仇彌浦 發覺 監司囚之 本郡馳報於是復爲刷還 麟雨率軍人五十名 備軍器齎三月粮 浮海而去 島在東海中 麟雨三陟人也
전 판장기현사(判長鬐縣事) 김인우(金麟雨)를 우산도(于山島)·무릉도(武陵島) 등지의 안무사(安撫使)로 삼았다. 당초에 강원도 평해(平海) 고을 사람 김을지(金乙之)·이만(李萬)·김울금[金亐乙金] 등이 무릉도에 도망가 살던 것을, 병신년에 국가에서 인우를 보내어 다 데리고 나왔는데, 계묘년에 을지 등 남녀 28명이 다시 본디 섬에 도망가서 살면서, 금년 5월에 을지 등 7인이 아내와 자식은 섬에 두고 작은 배를 타고 몰래 평해군 구미포(仇彌浦)에 왔다가 발각되었다. 감사가 잡아 가두고 본군(本郡)에서 급보(急報)하여 곧 도로 데려 내오기로 하고서, 인우가 군인 50명을 거느리고 군기와 3개월 양식을 갖춘 다음 배를 타고 나섰다. 섬은 동해 가운데 있고, 인우는 삼척(三陟) 사람이었다.
Kim In-u, a former panjanggihyeonsa, was made inspector for the Usan/Muleung region. In 1416, the government sent In-u to Muleungdo to bring back former Pyonghae residents Kim Ul-ji, Lee Man, Kim Ul-geum, and others who had run away to live on Muleungdo. In 1423, twenty-three men and women, including Ul-ji, ran away back to the island. In May this year, seven people, including Ul-ji, left their wives and children on the island and came secretly in a small boat to Kumi-po in Pyeonghae County, where they were discovered. The governor arrested them, and sent an urgent message from his village to bring back immediately the people still on the island. With fifty men, military equipment, and 3-months of rations, In-u got on a ship and left. The island is in the middle of the East Sea. In-u was from Samcheok.
So far, records have told us that there are two islands: Usan and Muleung. Records have also suggested that people have lived on both islands at one time or another, and that Usan was the larger of the two. However, if Usan was Ulleungdo and Muleung was a neighboring island, then one might wonder why the people mentioned in the above record chose to live on the smaller of the two islands? Was Muleung a specific reference to the smaller island or a general reference to the area? Or did the people prefer to live on the smaller island for security reasons or some other reason? It is unclear, but what is clear is that Muleungdo and Usando were either right next to each other or two names for the same island. Another thing that seems clear is that neither Muleungdo nor Usando was referring to Dokdo/Takeshima, which was too insignificant and too far away to cause the kind of name confusion that existed between Muleungdo and Usando.