280px, "Samguk Sagi" Book 04. Silla's Records.
In 512, Usan-guk（于山國）was Ulleungdo（鬱陵島） Usan-guk, or the State of Usan, occupied

Ulleung-do Ulleungdo (), also spelled Ulreungdo, is a South Korean island east of the Korean Peninsula in the Sea of Japan. It was formerly known as Dagelet Island or Argonaut Island in Europe. Volcanic in origin, the rocky steep-sided island is the top o ...

and the adjacent islands during the Korean Three Kingdoms period. According to the ''

Samguk Sagi ''Samguk sagi'' () is a historical record of the Three Kingdoms of Korea: Goguryeo, Baekje, and Silla. Completed in 1145, it is well-known in Korea as the oldest surviving chronicle of Korean history. The ''Samguk sagi'' is written in Classical ...

'', it was conquered by the

Silla Silla (; Old Korean: wikt:徐羅伐#Old Korean, 徐羅伐, Yale romanization of Korean, Yale: Syerapel, Revised Romanization of Korean, RR: ''Seorabeol''; International Phonetic Alphabet, IPA: ) was a Korean kingdom that existed between ...

general Kim Isabu in 512. He is said to have used wooden lions or tigers to intimidate the residents into surrendering. It has been written that the alias of Usan-guk is Ulleung-do. Usan-guk rarely entered into historical records, but appears to have continued a largely autonomous existence until its loss of independence to

Goryeo Goryeo (; ) was a Korean state founded in 918, during a time of national division called the Later Three Kingdoms period, that unified and ruled the Korea, Korean Peninsula until the establishment of Joseon in 1392. Goryeo achieved what has b ...

in 930.

History

Historical records

Earliest records that appear in the

Records of the Three Kingdoms The ''Records of the Three Kingdoms'' is a Chinese official history written by Chen Shou in the late 3rd century CE, covering the end of the Han dynasty (220 CE) and the subsequent Three Kingdoms period (220–280 CE). It is regard ...

indirectly attest the existence of the kingdom, which says "When Wang Qi () (of

Cao Wei Wei () was one of the major Dynasties in Chinese history, dynastic states in China during the Three Kingdoms period. The state was established in 220 by Cao Pi based upon the foundations laid by his father Cao Cao during the end of the Han dy ...

) has come to

Okjeo Okjeo () was an History of Korea, ancient Korean tribal state which arose in the northern Korea, Korean peninsula from perhaps the 2nd century BCE to the 5th century CE. Dong-okjeo (Eastern Okjeo) occupied roughly the area of the Hamgyong Provin ...

to conquer Kung (

Dongcheon of Goguryeo King Dongcheon (209–248, r. 227–248) was the 11th monarch of Goguryeo, the northernmost of the Three Kingdoms of Korea. Family *Father: King Sansang () **Grandfather: King Sindae () *Mother: ''Little Consort'' () *Consorts and their respe ...

), he asked a local man whether there are people living in the east sea, and the man replied there are people living in an island that exists in the eastern seas, and they select a girl to put in the ocean every July." In

, it is said that because of general Isabu's threats with wooden lions, Usan chose to be a vassal state to Silla in 512. In

Goryeosa ''Goryeosa'' (), or ''History of Goryeo'', is an extensive historical record of the Goryeo dynasty, compiled by the officials of Goryeo's successor state, Joseon. Its compilation started during the reign of Taejo of Joseon, Taejo (the founding ...

, it is recorded that Usan requested to be submitted under the rule of Goryeo in 930 by sending Paekkil () and T'odu ().

, Book 1 In 1018, when Usan was severely affected by Jurchen invasions, the Goryeo king sent Yi Wŏn'gwi () with farming equipment, and asked the locals of Usan who have fled from those invasions to return to their lands.

, Book4 Usan was finally abolished and fully incorporated in 1022 as all of the refugees from Usan were settled to the region of Yeju.

Old Korean maps

File:Ulleungdo and Usando.jpg, Joseon map (1530): Ulleungdo (鬱陵島) and Usan (于山島) File:Gwang Yeodo 18th century.jpg, 廣輿圖 (Gwang Yeodo,1737-1776)
This map showed Ulleungdo with a small island off its eastern shore labeled as "the so-called Usando" (所謂于山島). File:East of Ulleungdo and Usando.jpg, Kim Jeong-ho "Daedongyeojido" (1861): East of Ulleungdo (鬱陵島) and Usando (于山) File:DaehanJeondo.jpg, A map by

Korean Empire The Korean Empire, officially the Empire of Korea or Imperial Korea, was a Korean monarchical state proclaimed in October 1897 by King Gojong of the Joseon dynasty. The empire lasted until the Japanese annexation of Korea in August 1910. Dur ...

: Ulleungdo (鬱陵島) and Usan (于山)

References

{{DEFAULTSORT:Usan-Guk Former countries in Korean history Former monarchies of East Asia History of Korea States and territories established in the 510s 512 establishments 930s disestablishments States and territories disestablished in the 930s Island countries