Goryeo-Khitan War

Goryeo–Khitan War
Date 993, 1010, 1018-1019 Location Northern Korean Peninsula Result Goryeo victory The Khitan Liao dynasty cedes territory around the Yalu River basin to Goryeo Goryeo pays tribute to the Liao dynasty to establish diplomatic relations Peace ensues between Goryeo and Liao, and Liao never attacks Goryeo again
Belligerents
Goryeo	Liao dynasty
Commanders and leaders
King Hyeonjong Gang Gam-chan Seo Hui Gang Jo † Yang Gyu †	Emperor Shengzong Xiao Xunning Xiao Baiya
Strength
Second conflict: Approximately 300,000; Third conflict: Approximately 208,000	First conflict: Liao claimed 800,000 but the number is believed to be much lower; Second conflict: Approximately 400,000; Third conflict: Approximately 100,000

Goryeo victory

The Goryeo–Khitan War was a series of 10th- and 11th-century conflicts between Goryeo and the Khitan Liao dynasty near the present-day border between China and North Korea.

During the Three Kingdoms of Korea period, Goguryeo occupied the northern Korean Peninsula and parts of Manchuria and inner Mongolia. With Goguryeo's fall in 668, Silla unified the Three Kingdoms, while northern parts of Goguryeo territory were briefly occupied by Silla's ally, Tang China. A former Goguryeo general revived Goguryeo's Manchurian territory as the new kingdom of Balhae.

Right after the fall of Goguryeo, the Göktürks were divided and eventually driven out from most of Central Asia by the Tang. Another Turkic tribe, the Uyghurs, replaced the Göktürks, but their control was weak.

As Balhae, the Uyghur and the Tang Dynasty weakened, the Khitan people, a nomadic confederation in Manchuria and eastern Mongolia, grew stronger and began to expand their territory. Following Tang's fall in 907, China experienced a long period of civil war.

In 911, threatened by Khitan expansion, Balhae sought help from the declining Silla of the Korean Peninsula. Records stated that Balhae also requested help from Silla's successor dynasty Goryeo during the Later Three Kingdoms.

In 916, the Liao dynasty was founded by the Khitan chief Yelü Abaoji, who was enthroned as Emperor Taizu of Liao, replacing the Uyghurs as the dominant power of what is now Mongolia after the Yenisei Kirghiz and the Tang dynasty defeated the Uyghur Khaganate and left a power vacuum.

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