Gaeseong

Goryeo

Silla began to decline in the late 9th century, and a period of rival warlords ensued. In 898, Kaesong fell under the hand of Gung Ye, the founder of his short-lived state, Taebong, and then became a part of Goryeo in 919 by its founder, Wang Geon, who was enthroned as Taejo of Goryeo. Taejo established the capital in the south of Song'ak, and incorporated Kaesong into Song'ak under the name of "Gaeju". In 919, Kaesong became the national capital. In 960, the 11th year of Gwangjong of Goryeo's reign, the city was renamed Gaegyeong, and in 995, the 14th year of Seonjong of Goryeo's reign, it was elevated to "Gaesong-bu". The Gaeseong-bu is a combined term of Song'ak-gun, and Gaesong-gun, which is different from the region of the pre-1945 Gaesong-ri, Seo-myeon, Kaepung-gun. In 1010, the first year of Hyeonjong of Goryeo's reign, the palace and houses were almost burnt down during the second conflict in the Goryeo–Khitan War, so in 1018, Gaesong-bu was relegated for the "bu" system, and became to govern the three hyeon unites of Jeongju, Deoksu, and Gangeum.