Jeju uprising to Jeju from Busan and deploying police companies, each 1,700 strong, from the southern provinces of the mainland. The guerrillas retreated to their bases in the forests and caves around Hallasan, an extinct volcano and the highest mountain in South Korea. On April 29, the Korean, non-military, governor of Jeju province abandoned his post, defected, and joined the guerrillas. This caused many police officers, disillusioned by the atrocities they were ordered to commit against their own, to do the same. In response, U.S. military provincial governor William F. Dean ordered a purge of SKLP sympathizers from the ranks of the
Hallasan isolated from the mainland for a long time and its species were able to become unique and different from mainland species. The elevation of the mountain causes various plant species to live there. The mountain became a habitat for plants that live in low elevation and plants that live in high elevation. 50 or more unique species live in Jeju Island, especially in high elevation area in Hallasan. Various animal species also live on the mountain. Because of the geography of the mountain, the same species evolved in different ways after thousands of years. Just like plant species, animal species