KAIST

<(From Left) Professor Juyoung M. Park, Dr. Donghyeok Choi>

With the recent popularity of the film The King’s Warden, public interest has grown in the tragic history of King Danjong and Prince Suyang (later King Sejo), particularly surrounding Suyang’s Revolt of 1453 (the Gyeyu Coup). While the film dramatizes the political conflict, how did the fates of the real historical figures diverge? A joint team of KAIST and Hong Kong-based researchers has scientifically uncovered the patterns of success and downfall in Joseon’s bureaucratic society by analyzing data from the Annals of the Joseon Dynasty and Mungwa Bangmok, the higher civil service examination (gwageo) records.

KAIST (President Kwang Hyung Lee) announced on the 1st of April that a research team led by Professor Juyong M. Park of the Graduate School of Culture Technology, in collaboration with Dr. Donghyeok Choi (a KAIST alumnus) of Hong Kong Baptist University and the University of Hong Kong, analyzed the Annals of the Joseon Dynasty and Mungwa Bangmok using digital humanities and complex systems science methodologies. From these they were able to characterize the career patterns of over 14,600 Joseon officials.

<The original text of the Annals of the Joseon Dynasty from the time of the Gyeyu Jeongnan (left) and its online Korean translation (right)>

The team found that when Joseon’s recruitment system through gwageo was functional, its bureaucracy exhibited stability. When power became concentrated in oligarch families in the later period through abnormal means, however, inequality and stratification in the bureaucratic system intensified, ultimately leading to a national decline. In other words, the fall of Joseon was not the result of a single isolated event but can be seen as a consequence of a ‘systemic collapse,’ as demonstrated through data.

The Annals of the Joseon Dynasty, a globally recognized historical record spanning over 600 years, provides extensive data that allows for the precise reconstruction of political and social structures of the time. The researchers first conducted a quantitative analysis of the 1453 Revolt of Suyang, a dramatic event in early Joseon’s power structure. By constructing a network of officials connected to King Danjong, Prince Suyang (later King Sejo), and Prince Anpyeong during the event, they found data-driven findings that those closely aligned with Sejo were decorated, while those aligned with Anpyeong were purged.

<A network of connections among key royal figures of the Gyeyu Jeongnan—King Danjong, Grand Prince Suyang (later King Sejo), Grand Prince Anpyeong—and government officials, reconstructed from the records of the Annals>

But considering such a forced dethronement of a king was rare in Joseon’s history, the team turned to characterizing the more long-term features of the bureaucracy. To do this they developed a metric called “Total Success Index” that combines the rank of official positions held and the duration of service. The analysis then revealed that for approximately 400 years after the founding of Joseon, some positive correlation existed between individual background (family, regional origin, etc.) and individual success, but the correlation remained relatively stable, suggesting a certain degree of fairness and social mobility persisted.

<A Method for Defining a Bureaucrat’s Total Success Index Based on the Sum of Ranks Recorded in the Annals>

However, this stability began to disappear in the later Joseon period as powerful oligarch families such as the Andong Gims and Pungyang Jos passed higher civil service exams and assumed official positions through influence and power rather than competition, leading to a rapid intensification of inequality and stratification within the bureaucracy, indicating the breakdown of the traditional recruitment system. The researchers observed that Joseon society, unable to resolve these issues, ultimately declined and collapsed.

<A Correlation Between the Total Success Index Calculated from the Annals and the Region and Family Background Recorded in the Civil Service Examination Rosters>

Professor Juyong M. Park stated, “This study tries to go beyond the limitations of focusing on short-term historical events, examining the long-term structural changes across the entire history of a nation,” adding, “Understanding how individual and group actions influence the rise and fall of a state provides important insights into issues of fairness and talent recruitment, relevant to this modern day.”

<A Diagram Illustrating the Domination of the Bureaucracy by Specific Families (the Andong Kim, Pungyang Jo, Yeoheung Min, and Bannam Park Clans) in the Late Joseon Period>

He further added, “The integration of digitized historical data and scientific data analysis will become a key tool not only for understanding the past but also for guiding the future of society.”

The research team now plans to expand the Joseon historical database using artificial intelligence (AI), compare Joseon’s bureaucratic system with other countries’, and analyze the records of international interactions to further explore the global historical significance of Joseon.

This study was conducted with Dr. Donghyeok Choi (Ph.D. graduate of KAIST’s Graduate School of Culture Technology) as the first author, published in the April issue of Physica A: Statistical Mechanics and Its Applications.
 ※ Paper title: “Total Success Index and the Longitudinal Dynamics of Bureaucratic Stratification in Joseon Korea” (https://shm.to/bYJ0SBo) / DOI: 10.1016/j.physa.2026.131353

This research was supported by the National Research Foundation of Korea’s interdisciplinary research program, the Humanities and Social Science Research Institute Support Program, the BK21 Phase 4 Program, the Korea Creative Content Agency’s R&D program for copyright service innovation, KAIST’s Post-AI program, and the Korea Institute for Advanced Study (KIAS).