Tsushima Island dispute

The Tsushima/Daemado Island dispute concerns a territorial issue about Tsushima Island, a large island in the Korea Strait between the Korean peninsula and the island of Kyushu. The island is known as the Daemado in Korean.South Korea does not officially claim the island though some South Koreans have said that Korea has a historical claim on the island and have taken steps to attempt to assert South Korean ownership.

Sanguozhi, the official historical records of the Three Kingdoms period of China (220–280 A.D.) written in the third century, recorded that the island was an ancient country of Wa (Japan).

When the ancient law system Ritsuryō of Japan was established (somewhere between 645 and 701 A.D.), Tsushima Province formally became a province of Japan. Since then, Tsushima Province has been a part of Japan, except for the temporary occupation by Mongol Empire in the Mongol invasions of Japan (1274 and 1281).

The island was described by Hayashi Shihei in Sangoku Tsūran Zusetsu, which was published in 1785. It was identified as part of Japan.

In 1946, the Supreme Commander for the Allied Powers (SCAP) defined Japan to include the four main islands and approximately 1000 nearby islands, including Tsushima.

In 1948, the Republic of Korea (ROK) asserted its sovereignty over the island based on "historical claims". In 1949, the SCAP rejected South Korea's claim.

In 1951, United States-Korea negotiations about the Treaty of San Francisco made no mention of Tsushima Island. After this, the status of Tsushima as an island of Japan was re-confirmed by the US.

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