Jang Bogo's downfall originated in a power struggle within the Silla royal court. He became deeply entangled in a succession dispute and, in doing so, made himself a target for his political rivals. In 846, he was assassinated by an agent named Yeomjang. In the aftermath of his death, Cheonghaejin's standing collapsed rapidly. The Silla court no longer trusted this power that even the royal family had once struggled to control, and among Cheonghaejin's own residents, resentment grew steadily toward a court that had eliminated Jang Bogo.
In 851 (the 13th year of King Munseong's reign), the Silla court forcibly relocated Cheonghaejin's residents to Byeokgol-gun, an area corresponding to today's Gimje in North Jeolla Province, and abolished the garrison. The dated record supports the year, destination, relocation, and abolition; it does not provide a precise number of people moved. The institution established in 828 therefore lasted 23 years, while the physical site and its archaeological remains did not simply vanish.
The History of Korea database's Samguk sagi text records the abolition in the second lunar month of 851 and transfer to Byeokgol County. The Encyclopedia of Korean Culture explains that Jang Bogo's descendants and officers tried to maintain overseas trade before the central government eliminated the remaining organization. Cheonghaejin survived for several years after Jang's death. The primary record does not support attaching a precise modern headcount to every displaced person, so this edition gives the year and destination without inflated figures. The map point remains Cheonghaejin because Gimje was the destination, not the Wando scene. Stories 1 and 2 share a place but ask different questions.