Jalairtai Qorchi ravaged Korea. When one of Yeku's envoys arrived, Gojong personally met him at his new palace in Sin Chuan-bug. Gojong finally agreed to move the capital back to the mainland, and sent his stepson Angyeong as a hostage. The Mongols agreed to a cease fire in January 1254. Sixth Mongol invasion of Korea (July 1254 – December 1254) The Mongols later learned that top Goryeo officials remained on Ganghwa Island, and had punished those who negotiated with the Mongols. Between 1253 and 1258, the Mongols under Jalairtai launched four devastating invasions in the final successful campaign against Korea. Möngke realized that the hostage was not the blood prince of the Goryeo Dynasty. So Möngke blamed the Goryeo court for deceiving him and killing the family of Lee Hyeong, who was a pro-Mongol Korean general. Möngke' commander Jalairtai devastated much of Goryeo and took 206,800 captives in 1254. Famine and despair forced peasants to surrender to the Mongols. They established a chiliarchy office at Yonghung with local officials. Seventh Mongol invasion of Korea (September 1255 – June 1256) Ordering defectors to build ships, the Mongols began attacking the coastal islands from 1255 onward. In the Liaodong Peninsula, the Mongols eventually massed Korean defectors into a colony of 5,000 households. Mongke Khan once again sent a large army along with Prince Yeongnyeong and Hong Bok-won, who had been taken hostage by Jalaltai as the captain, and gathered at Gapgot Daedan (甲串岸) and showed momentum to attack Ganghwa Island. However, Kim Sugang (金守剛), who had just gone to Mongolia, succeeded in persuading Mongke Khan, and the Mongols withdrew from Goryeo. Eighth Mongol invasion of Korea (May 1257 – October 1257) In 1258, Goryeo's King Gojong and one of the retainers of the Choe clan, Kim Injoon, staged a counter-coup and assassinated the head of the Choe family, ending the rule of the Choe family which spanned six decades. Afterwards, the king sued for peace with the Mongols. When the Goryeo court sent the future king Wonjong as hostage to the Mongol court and promised to return to Kaegyong, the Mongols withdrew from Central Korea. There were two parties within Goryeo: the literati party, which opposed the war with the Mongols, and the military junta—led by the Choe clan—which pressed for continuing the war. When the dictator Choe was murdered by the literati party, the peace treaty was concluded. The treaty permitted