In 1398, upon hearing of this plan, Yi Bang-won immediately revolted and raided the palace, killing Jeong Do-jeon, 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 crown, and psychologically exhausted from the death of his second wife, King Taejo immediately crowned his second son Yi Bang-gwa, later King Jeongjong, as the new ruler. Thereafter, King Taejo retired to the Hamhung Royal Villa. After that, he maintained distance with Yi Bang-won. Doing so provoked huge rampage from Taejo, because both the two sons and Jeong Do-jeon were whom he favored. Allegedly, Yi Bang-won sent emissaries numerous times, and each time Taejo killed them to express his firm decision not to meet his son again. This historical anecdote gave birth to the term "Hamhung Cha sa", which means a person who never comes back despite several nudges. But recent studies have found that Taejo in fact did not kill any of those Hamung emissaries. Those subjects were killed during revolts, which coincidentally occurred in the Hamhung region.