While many people are aware of the Mongol invasions of Korea and subsequent failed attempts to invade Japan in the 13th century, few people are aware of the role Jeju played – specifically related to the Three Patrol Revolt which began on Kangwha Island and made its way south.
The Sambyeolcho (henceforth referred to as rebels) closed off the island from the mainland and seized weapons from the government armory. A lesser member of the royal family, known only as Wang On, was chosen as the new king, but he appears to have been merely a figurehead – a puppet to be used by General Bae.
It was clear that the rebels would be unable to hold Kangwha Island (its fortifications having earlier been dismantled in compliance with the Mongol demands) against the combined forces of the Goryeo and Mongol armies. So, on June 23, they plundered the island’s treasures, took the women and children of the officials as hostages, and sailed away from the island in an enormous armada of over 1,000 ships.
When the Kangwha Island officials (those who had gone to welcome Wonjeong’s return) discovered that their families had been taken hostage, “their bitter weeping rent heaven and earth,” but there was little anyone could do.
You can read the rest of the article at Jeju Weekly.