Early life The future King Taejo was born in
Ssangseong Prefecture on the frontiers of the
Yuan dynasty. Taejo's father was
Yi Chach'un, an official of Korean ethnicity serving the
Mongol-led Yuan. His mother,
Lady Ch'oe, came from a family originally from Deungju (present-day
Anbyŏn County, North Korea). In 1356, the Yi family defected to Goryeo, helping Goryeo seize control of Ssangseong Prefecture from its governor, Cho So-saeng.
Historical context By the late 14th century, the 400-year-old
Goryeo dynasty established by
Wang Kŏn in 918 was tottering, its foundations collapsing from years of war and
de facto occupation by the disintegrating
Mongol Empire. The legitimacy of the royal family itself was also becoming an increasingly disputed issue within the court. The
ruling house not only failed to govern the kingdom effectively but was also affected by rivalry among its various branches and by generations of
forced intermarriage with members of the Yuan imperial family.
King U's biological mother being a known
slave led to rumors contesting his descent from
King Gongmin. Influential aristocrats, generals, and ministers struggled for royal favor and vied for domination of the court, resulting in deep divisions between various
factions. With the ever-increasing number of raids against Goryeo conducted by
Japanese pirates and the
Red Turbans, those who came to dominate the royal court were the reform-minded
Sinjin faction of the
scholar-officials and the opposing
Gwonmun faction of the old
aristocratic families as well as generals who could actually fight off the foreign threats—namely Yi Sŏnggye and his rival
Ch'oe Yŏng. As the
Ming dynasty started to emerge, the Yuan forces became more vulnerable, and Goryeo regained its full independence by the mid-1350s although Yuan remnants effectively occupied northeastern territories with large garrisons of troops.
Military career Yi Sŏnggye started his career as a military officer in 1360 and would eventually rise up the ranks. General Yi had gained prestige during the late 1370s and early 1380s by pushing Mongol remnants off the peninsula and also by repelling the well-organized Japanese pirates in a series of successful engagements. Envoys were also dispatched to Japan, seeking the re-establishment of amicable connections. The mission was successful, and
Ashikaga Yoshimitsu was reported to have been favorably impressed by this embassy. When the new dynasty was officially promulgated, the issue of which son would be the heir to the throne was brought up. Although Yi Pang-wŏn, Taejo's fifth son by his first wife
Queen Sinui, had contributed the most to his father's rise to power, he harbored a profound hatred against two of Taejo's key allies, Chŏng To-jŏn and
Nam Ŭn. Both sides were fully aware of the mutual animosity and felt constantly threatened. When it became clear that Yi Pang-wŏn was the most worthy successor, Chŏng To-jŏn, who had met and formed a political alliance with
Queen Sindeok prior, used his influence to convince the king that the wisest choice would be the son that he loved most, not the son that he felt was best for the kingdom. In 1392, the eighth son of King Taejo and his second son by Queen Sindeok,
Yi Pang-sŏk, was appointed as crown prince. After the sudden death of the queen in 1396 and while Taejo was still in mourning for his wife, Chŏng To-jŏn began conspiring to preemptively kill Yi Pang-wŏn and his brothers to secure his position in the royal court. Upon hearing of this plan in 1398, Yi Pang-wŏn and his wife,
Princess Jeongnyeong, immediately revolted and raided the palace, killing Chŏng To-jŏn, his followers, and the two sons of the late Queen Sindeok. This incident became known as the First Strife of Princes (). Aghast at the fact that his sons were willing to kill each other for the throne and psychologically exhausted by the death of his second wife, Taejo immediately named his second son,
Yi Pang-gwa (posthumously King Jeongjong), as the new successor and abdicated. Thereafter, Taejo retired to the
Hamhung Royal Villa and maintained distance with his fifth son for the rest of his life. Allegedly, Yi Pang-wŏn sent emissaries numerous times and each time the former king executed them to express his firm decision not to meet his son again. This historical anecdote gave birth to the term
Hamhung Chasa () which means a person who never comes back despite several nudges. However, recent studies have found that Taejo did not actually execute any of the emissaries; these people died during revolts which coincidentally occurred in the region. In 1400, King Jeongjong named Yi Pang-wŏn as heir presumptive and voluntarily abdicated. That same year, Yi Pang-wŏn assumed the throne of Joseon; he is posthumously known as King Taejong.
Death King Taejo died ten years after his abdication on 27 June 1408 in
Changdeokgung. He was buried at Geonwolleung () in the
Donggureung Cluster (present-day
Guri, South Korea). The
tomb of his umbilical cord is located in
Geumsan County, South Korea. ==Legacy==