Mourning Rite Disputes
Twice, on the deaths of Hyojong and his queen, the Westerners and Southerners clashed over how long the dowager queen should wear mourning; the Westerners won in 1659, the Southerners in 1674.
Yi Myeong-gi · Public domain · Source
Gihae dispute (1659): when Hyojong died, the Westerners (Song Si-yeol) argued for one year of mourning since he was a second son; the Southerners (Heo Mok, Yun Hyu) for three years since as king he counted as the eldest son. The one-year view prevailed.
Gabin dispute (1674): when Hyojong’s queen died, the Westerners argued for nine months, the Southerners for one year; Hyeonjong sided with the Southerners, who took power.
Framed as a debate over Neo-Confucian ritual, it was really about Hyojong’s legitimacy and royal authority: the Westerners held that the king followed the same rites as the scholar-officials, the Southerners that royal rites were distinct.