Korea is a region and nation-state on the planet Earth, located on the eastern coast of the continent of Asia.
History
Following the devastation of the 20th century's Second World War, Korea was divided into two countries—North Korea, which was backed by the Soviet Union and its allies, and South Korea, which was backed by the United States of America and its United Nations allies. From the years 1950 to 1953, North and South Korea fought in a conflict which would come to be known as the Korean War.
Angela Franklin, a 20th century engineer, served in the United States Army Corps of Engineers in Korea from 1958 to 1961. (TOS - Star Trek: Assignment: Earth comic: "Brighter Than a Thousand Suns")
In 2376, Elias Vaughn had a second orb experience with a Bajoran orb. In this experience, Vaughn became Eli Underwood, a veteran of the Korean War. Underwood was present when the UN-allied forces retook Seoul. (DS9 novel: Unity)