History of Cheju-do

On April 3, 1948, against a background of an ongoing ideological struggle for control of Korea and a variety of grievances held by islanders against the local authorities, the many communist sympathizers on the island attacked police stations and government offices. The brutal and often indiscriminate suppression of the leftist rebellion resulted in the deaths of tens of thousands of both villagers and communist radicals and the imprisonment of thousands more in internment camps.

While claims have been made that the US government oversaw and supported "anti-communist" activities administratively if not openly in the field, validation remains to be made. It is a fact the US was heavily involved in counter insurgence operations across Korea at this time leading up to the Korean War and UN involvement. Similarly, the Northwest Youth League, a Korean government sponsored watch-dog group made up of refugees who had fled northern Korea, actively repressed any and all "communist sympathizers" with an ardent campaign of shooting anyone on sight entering or leaving the president's "enemy zone", raping/violation, torturing, and killing hundreds of islanders using open armed violence and what would be labeled today as terrorist activities. Intolerance by mainland Korean officials of islanders in general at the time, government and organization sponsored isolation of the island,