Goryeo and Joseon

Goryeo (Korean: 고려; Hanja: 高麗; Middle Korean: 고ᇢ롕〮, romanized: kwòwlyéy) was a Korean state founded in 918, during a time of national division called the Later Three Kingdoms period, that unified and ruled the Korean Peninsula until the establishment of Joseon in 1392. Goryeo achieved what has been called a "true national unification" by Korean historians, as it not only unified the Later Three Kingdoms but also incorporated much of the ruling class of the northern kingdom of Balhae, who had origins in Goguryeo of the earlier Three Kingdoms of Korea. According to Korean historians, it was during the Goryeo period that the individual identities of Goguryeo, Baekje and Silla were successfully merged into a single entity that became the basis of the modern-day Korean identity. The name Korea is derived from the name of Goryeo, also romanized as Koryŏ, which was first used in the early 5th century by Goguryeo; Goryeo was a successor state to Later Goguryeo and Goguryeo.

Joseon (English: CHOH-sun; Korean: 조선; Hanja: 朝鮮; also romanized as Chosun), officially Great Joseon State (대조선국; 大朝鮮國), was a dynastic kingdom of Korea that existed for 505 years. It was founded by Taejo of Joseon in 1392 and replaced by the Korean Empire in 1897. The kingdom was founded after the overthrow of Goryeo in what is today the city of Kaesong. In 1393, Korea was retitled and the capital was moved to modern-day Seoul. The kingdom's northernmost borders were expanded to the natural boundaries at the rivers of Amnok and Tuman through the subjugation of the Jurchens.