The setting of Destiny of Rebirth is in the Yuan Dynasty, and at that time the state of Goryeo (高麗) was in reign, not Chosŏn. Goryeo 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 1392.
Chosŏn, officially Great Joseon, was founded by Yi Seong-gye in July 1392 and was the last dynastic kingdom of Korea, lasting just over 500 years. The kingdom was founded following the aftermath of the overthrow of Goryeo in what is now known as the city of Kaesong. Early on, Korea was retitled, and the capital was relocated to modern-day Seoul. The kingdom’s northernmost borders were expanded to the natural boundaries at the rivers of Amrok and Tuman through the subjugation of the Jurchens. It was later replaced by the Korean Empire in October 1897. (https://en.wikipedia.org/wiki/Goryeo)
Fig. 1 Map of Goryeo in 1389
Fig. 2 Goryeo’s conquest of Silla and Later Baekje
