Question: who is yi bang won?
Answer: Jeongjong of Joseon (18 July 1357 – 15 October 1419), born Yi Bang-gwa, whose changed name is Yi Gyeong, was the second king of Joseon (or Chosun) Dynasty (1399–1400). He was the second son of King Taejo of Joseon, the founder and first king of the dynasty.