Sukjong’s Changes of Power (Hwanguk)
Three times Sukjong replaced the ruling faction wholesale (1680, 1689, 1694); along the way the Westerners split into the Noron and Soron.

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Gyeongsin (1680): the Southerner chief minister Heo Jeok used a royal tent without leave and his son was implicated in treason; the Southerners were ousted and the Westerners took power, then split over punishing the Southerners into the hard-line Noron (Song Si-yeol) and moderate Soron (Yun Jeung).
Gisa (1689): the Westerners who opposed naming Royal Consort Jang’s son (the future Gyeongjong) as heir were ousted and the Southerners returned; Song Si-yeol was forced to take poison and Queen Inhyeon was deposed.
Gapsul (1694): when the Southerners suppressed a movement to restore Queen Inhyeon, Sukjong expelled them and recalled the Westerners; the Southerners never held power again. These reversals brought one-faction rule and vengeful purges, undoing the balance of factional politics.
