Crown Prince Jeongseong

Wang Seok
Prince Jeongseong
(정성군; 定城君)
Reign1388–1389
Coronation1388
Crown Prince of Goryeo
Reign1389 – July 1392
Coronation1389
PredecessorCrown Prince Wang Jeong
SuccessorDynasty abolished
(Yi Bangu as the first Crown Prince of Joseon)
MonarchKing Gongyang (father)
BornWang Dan
1370
Goryeo
Died1394 (aged 24)
Samcheok, Gangwon Province, Joseon
Spouse
Crown Princess Consort of the Incheon Yi clan
(m. 1391⁠–⁠1394)
HouseHouse of Wang
FatherGongyang of Goryeo
MotherRoyal Consort Sun of the Gyoha No clan
ReligionBuddhism
Korean name
Hangul
왕석
Hanja
王奭
RRWang Seok
MRWang Sŏk
Royal title
Hangul
정성세자
Hanja
定城世子
RRJeongseong seja
MRChŏngsŏng seja
Former names
Hangul
왕서, 왕단
Hanja
王瑞, 王瑞
RRWang Seo, Wang Dan
MRWang Sŏ, Wang Tan

Crown Prince Jeongseong (ca. 1370–1394) or known before as Prince Jeongseong, was the first son of King Gongyang and Consort Sun who would eventually become the last Crown Prince of the Goryeo dynasty. After Yi Seonggye established the new dynasty, he was deposed from his throne along with his parents and got assassinated. His birth name was Wang Dan (왕단; 王瑞), but later changed to Wang Seok (왕석; 王奭) whom he was better known as.