Goryeo, also spelled as Koryŏ, was a Korean dynasty established in 918 by King Taejo. This kingdom later gave name to the modern exonym Korea and it united the Later Three Kingdoms in 936 and ruled most of the Korean Peninsula until it was removed by the founder of the Joseon in 1392. Goryeo expanded Koreas borders to present-day Wonsan in the northeast, the Yalu River, two of this periods most notable products are celadon pottery and the Tripitaka Koreana—the Buddhist canon carved onto more than 80,000 woodblocks and stored at Haeinsa. The people of Goryeo also created the first metal type that was capable of printing actual books, in 1234, the oldest surviving metal movable type book. A son of a lord, Wang Geon, joined Taebong as a general. Taebong fell when Wang Geon revolted and killed Gung Ye in 918, Silla was overpowered by Goryeo and Later Baekje and surrendered to Goryeo in 935. By the late 13th century, after nearly 30 years of warfare with the Mongols of the Yuan dynasty, Goryeo lost much of its power, the name Goryeo is derived from Goguryeo of the Three Kingdoms of Korea, which the Goryeo state regarded as its predecessor. Goguryeo changed its name to Goryeo during the reign of Jangsu in the 5th century, the English name Korea derives from Goryeo. Silla, which had accomplished an incomplete unification of the Three Kingdoms of Korea in 668, weakened, the country entered a period of civil war and rebellion, led by Gung Ye, Gi Hwon, Yang Gil, and Gyeon Hwon. Gung Ye established the state of Later Goguryeo, renamed Taebong, together with the declining Later Silla, they are known as the Later Three Kingdoms. Wang Geon, who became the Taejo of Goryeo, joined Later Goguryeo as a general but later overthrew Gung Ye. Goryeo regarded itself as the successor of Goguryeo, Wang Geon, the founder of Goryeo, was a descendant of Goguryeo, and traced his ancestry to a noble Goguryeo clan. For three years after, Later Baekje dominated the Later Three Kingdoms, but after a defeat at Andong in 930, the Later Three Kingdoms era ended when Goryeo annexed Silla in 935 and defeated Later Baekje in 936. King Taejo moved the capital to his hometown of Kaesǒng, Taejo married a daughter of the Silla royal family and allowed most of their nobility to keep their lands. Even though he ruled the nation for only seven years before his son took the throne upon his death. The terminology used in the court of Goryeo was that of an empire, the capital, Gaegyeong was called Hwangdo Imperial Capital and the palace was referred to as Imperial Palace. The nation also utilized a system of multiple capitals, Gaegyeong as the main capital, the mere use of this system and the nomenclature or use of the character 京 implied that Goryeo functioned internally as an empire. Other terms, such as Your Imperial Majesty, Empress Imperial Crown Prince, Empress Dowager, however, Goryeo, when enshrining its rulers, did not use the title Emperor
Illustration of Maitreyavyakarana-sutra(彌勒下生經變相圖)
Wang Geon (877-943), the founder of Goryeo dynasty
A Goryeo painting depicting the Imperial Palace of Goryeo.