Wang Kŏn’s Goryeo gave Korea its modern English name
Goryeo, founded in 918 amid the Later Three Kingdoms, unified the peninsula until Joseon replaced it in 1392. General Wang Kŏn (Taejo) seized power from Taebong’s erratic Kung Ye; the state’s name, borrowed from earlier Goguryeo, is the source of “Korea.”
Goryeo grew out of a fractured peninsula. Silla had absorbed its rivals in the late seventh century and tried to fold in refugees from Baekje and Goguryeo, even building a central army, the Ku-sŏdang, with separate units of Silla, Goguryeo, Baekje and Mohe soldiers. The refugee communities never lost their grudges, and in the north, around what is now Kaesong, Goguryeo loyalists eventually formed Later Goguryeo. Wang Kŏn came from a powerful seafaring family in Kaesong that claimed Goguryeo descent. He joined the warlord Kung Ye at 19 in 896 and made his name raiding the Later Baekje coast by sea, seizing places such as Naju.
Kung Ye grew erratic and cruel, shifting his capital to Cheorwon in 905 and renaming his state Majin in 904 and Taebong in 911. In 918 fellow generals chose Wang Kŏn to replace him. The new kingdom claimed Goguryeo's inheritance, including its name: Goguryeo, Later Goguryeo and Goryeo all called themselves Goryeo, and the distinct labels were fixed by the Samguk sagi in the twelfth century. The name, possibly from words for high and castle, is where Korea comes from. Korean historians call the result a true national unification because it also took in much of Balhae's elite and merged Silla, Baekje and Goguryeo identities into one.
Buddhism was the state religion and reached its peak influence, with some 70 temples in the capital by the eleventh century. Kaesong was a hub of trade and craft, drawing merchants from as far away as the Middle East, and the era is remembered for major achievements in art.
Security was a constant struggle. Goryeo fought the Khitan Liao and Jurchen Jin, fell to the Mongols and served the Yuan as a vassal in the thirteenth and fourteenth centuries, then struck back as the Yuan weakened, a push modern scholars link to a doctrine of recovering Goguryeo's old northern lands. In its last decades it beat off Red Turban armies and Japanese pirates. A planned strike on Ming China ended instead in General Yi Sŏnggye's coup, and Joseon replaced Goryeo in 1392.
Source: Goryeo
