Paramount leader represents the de-facto leader of Korea whereas the Head of State refers to the nominal leader of Korea such as the Emperor or the President. After 1988, both the paramount leader and the head of state are the same for the Republic of Korea for simplicity.
Yellow represents the Joseon Dynasty
Grey represents foreign occupation (Japanese, American, and Soviet) and the heads of state refer to the heads of state of that country
Dark red represents Conservative and Military governments, blue represents liberal governments, and red represents the Worker's Party of Korea