Battle of Gongsan

Overview

The Battle of Gongsan (Battle of Gongsan Dongsu) was fought in 927 (Taejo 10 of Goryeo, Year 4 of King Gyeongae of Silla) at Gongsan Dongsu (桐藪), in the present-day Palgongsan area of Dong-gu, Daegu, where the army of Gyeonhwon of Later Baekje decisively defeated the army of Wang Geon, Taejo of Goryeo. After Gyeonhwon had ravaged the Silla royal capital and was returning, Taejo personally led 5,000 cavalry to intercept him, but was instead surrounded. Generals including Shin Sung-gyeom and Kim Rak were killed, and Taejo narrowly saved his life. Following this victory, Later Baekje held the initiative among the Later Three Kingdoms for a time.

The dates in this article are according to the lunar calendar. The Goryeosa records this series of events together in the ninth month of Taejo's 10th year (the ninth lunar month corresponds to late September through late October in the solar calendar).

Background

Goryeo and Later Baekje made peace in 925 after a standoff at Jomulseong, exchanging hostages. However, in 926 Jinho, a nephew of Gyeonhwon who had been sent to Goryeo as a hostage, suddenly died, and Gyeonhwon killed Wang Sin, a Goryeo hostage held by Later Baekje, thereby breaking the peace. In the first month of 927, Taejo attacked Yongju (Yongung, present-day Yecheon) of Later Baekje and forced its surrender; at this time King Gyeongae of Silla sent troops to aid Goryeo. Goryeo then successively attacked Unju, Geunpumseong, Gangju, Daeryangseong, and other places. As Silla leaned toward Goryeo, Gyeonhwon decided to attack Silla directly.

Course of Events

Raid on the Silla Royal Capital

In the ninth month of 927, Gyeonhwon attacked Geunpumseong (present-day Sanbuk, Mungyeong), burned it, and raided Silla's Goulbu (present-day Yeongcheon), advancing to the outskirts of the royal capital. King Gyeongae sent Yeonsik to Goryeo to urgently request aid. Taejo said, "Silla and we have long been on friendly terms, so we cannot fail to rescue them in a crisis," and sent Si-jung Gong Hwon, Daesang Son Haeng, Jeongjo Yeon Ju, and others with 10,000 troops.

However, before the relief force arrived, Gyeonhwon suddenly invaded the Silla capital. According to the Goryeosa, King Gyeongae, together with his queen and royal relatives, was holding a drinking party at Poseokjeong and was unaware that enemy soldiers had broken in. The king and queen fled and hid in a secondary palace to the south of the city but were captured, and Gyeonhwon forced the king to take his own life in the army's camp. Gyeonhwon installed the king's first cousin, Kim Bu, as king; he became King Gyeongsun. He then took the king's younger brother Hyoryeom, the minister Yeonggyeong, and others as prisoners, and gathered up the children of the common people, artisans, weapons, and treasures before returning.

The Decisive Battle at Gongsan Dongsu

On hearing the news, Taejo was greatly enraged. He sent an envoy to Silla to offer condolences and personally led 5,000 elite cavalry to meet Gyeonhwon, who was returning, at Gongsan Dongsu and fought him. Encyclopedia of Korean Culture describes Dongsu as the area around present-day Donghwasa Temple, while Korean Wikipedia places it in the area of Jimyo-dong. The battle developed unfavorably for Goryeo, and the Later Baekje army closed in around Taejo in multiple layers. The commanders Shin Sung-gyeom and Kim Rak fought fiercely but were killed, the Goryeo army collapsed and fled, and Taejo barely escaped with his life.