Injo coup

King Gwanghae (光海君, 광해군) was an outstanding administrator and great diplomat, he was largely unsupported by many politicians, scholars, and aristocrats because he was not the first-born and he was born of a concubine. Greater Northerners tried to stomp out those opinions, suppressing Lesser Northerners and killing Prince Imhae (臨海君, 임해군), the oldest son of Seonjo, and Grand Prince Yeongchang (永昌大君, 영창대군), the queen's son. It was not Gwanghae's plan to keep his throne; and in fact, he actually tried to bring minor factions into the government, but was blocked by opposition from members of the Greater Northerners, such as Jeong In-hong and Yi Icheom. The actions made Gwanghae even more unpopular among wealthy aristocrats, and they finally began plotting against him.

In 1623, members of the ultra-conservative Westerners faction, Kim Ja-jeom, Kim Ryu, Yi Gwi and Yi Gwal, launched a coup that resulted in the dethroning of Gwanghae, who was sent into exile on Jeju Island. Jeong In-hong and Yi Icheom were killed, and followed suddenly by the Westerners replacing the Greater Northerners as the ruling political faction. The Westerners brought Prince Neungyang to the palace and crowned him as King Injo. Although Injo was king, he did not have any authority since almost all of the power was held by the Western faction that dethroned Gwanghae.