Changes in informal society and slavery during the Chosun-Era in Korea

The study investigates how the 1731 shift from the Jongcheon to the Jongyang law (making slave status matrilineal) altered the institution of slavery in Chosun-era Korea. The authors pose the hypothesis that the legal change increased slave desertions, raised owners’ monitoring costs, reduced slave demand and prices, and accelerated substitution of slave labor with wage labor. Contextually, Korean slavery differed from Atlantic systems: slaves were native, culturally indistinguishable from commoners, and both public and private slavery existed within a rigid hereditary status order. The introduction outlines the demographic prominence of slavery (25–40% before 1731), the rapid decline thereafter, and posits political drivers behind the reform. It frames the core question: did regulation-induced desertions catalyze an informal, market-driven collapse of slavery and contribute to broader social-economic changes?

The paper links slave desertion to informal-sector dynamics through social network theory. In informal sectors with low social capital and limited trust, markets are fragmented, information flows poorly, and credit costs are high; Korea’s agricultural loan rates (35–50%) far exceeded Europe’s (2–10%) in the period. The author argues slaves, excluded from institutions (property, marriage, official employment, social security), fled into these informal niches, aided by mountainous geography and small-plot agriculture. The literature on Korean slavery is summarized in two strands: legal-institutional changes (Pyung; Park; Jeon; Choi; Ji) and demographic studies using household tallies and elite records (Shikata; Chong; Han; Choi; Park; Hong; Lee), with Palais and Patterson providing English overviews. Broader debates on slavery efficiency (Conrad & Meyer; Fogel & Engerman vs. David & Temin) are noted; Korean transaction evidence has been sparse (Chong; Lee). The paper positions its contribution as empirically tracing desertion’s role in institutional change via prices and desertion data, contrasting Korea’s trajectory with the Atlantic world.

Data sources and measures: The study uses official household tally registers from three counties in Kyungsang province—Danseong (registers for 1678–1789, 1825–1832, 1861), Eonyang (registers for 1777, 1795, 1813, 1825, 1858, 1861), and Daegu (the Daegu-Choi family’s Danja, semi-register, and official tally 1672–1801). These registers record household members, slaves, arrivals, departures (moved, deserted, died), and exemptions. Slave desertion rates are calculated from these tallies. Monitoring costs are unobservable; the study proxies them using real slave prices derived from 634 private slave transactions (1690–1893) collected from over 25 historical sources (Kim and Lee, 2007), deflated by rice prices (rice was a key medium of exchange; 1 suk = 80 kg). Population data are from Kwon and Shin (1977), acknowledging potential measurement error. Daily farm wages from the Park family records are converted to annual by assuming 25 days per month and 10 months per year. Econometric strategy: The core model regresses ln(real slave price) on ln(desertion rate), ln(slave population), and a post-1731 regulation dummy. Real slave prices are interpreted as inverse monitoring costs (lower prices imply higher monitoring costs). Robust cluster GLS is first applied; due to suspected measurement error/endogeneity in slave population (itself influenced by desertion), a two-stage least squares panel approach is used. First stage estimates slave population using instruments: slave prices, desertion rate, and the 1731 dummy. The second stage re-estimates the main equation replacing slave population with its IV-predicted values. Diagnostics include VIF, Breusch-Pagan test for heteroscedasticity, F-statistics, and R-squared. Descriptive analyses of desertion rates, slave populations, and substitution with wage labor (ratios of slaves to wage workers in Eonyang) complement the regressions.

- Legal change and desertion dynamics: The 1731 Jongyang law coincided with sharp increases in slave desertion. In the Daegu-Choi family, slaves fell from 157 (1731) to 73 (1801); desertion rates rose from 12.5% (1681) to 56.1% (1801), averaging 20.8% (1672–1801). In Danseong county, desertion rates reached 33.8% (1732) and 37.0% (1783), then declined to 21.3% (1825) and 17.1% (1861) after public slavery’s abolition in 1801; slave population decreased from 6,233 (1729) to 2,145 (1825). In Eonyang, desertion rates were 11.5% (1777), 14.1% (1798), dropping to 8.7% (1813), 5.0% (1825), 4.6% (1861). - Prices as monitoring-cost proxy: Real slave prices declined markedly between 1731 and 1801, moving inversely with desertion rates. Average real prices equaled 8.85 suk (≈708 kg rice). Between 1731 and 1801, real prices fell by 42% (from 11.88 to 6.89 suk), consistent with rising monitoring costs from desertion. - Econometric results: Robust GLS finds the 1731 regulation dummy significantly reduces real slave prices; desertion and slave population are not significant in GLS. Panel 2SLS (addressing endogeneity/measurement error in slave population) shows both ln(desertion) and the 1731 dummy have significant negative effects on real slave prices (coefficients approx. −20.20 for desertion and −21.15 for the dummy; 5% significance), while predicted slave population remains insignificant at 5%. Model fit improves (R² ≈ 0.82; Root MSE ≈ 2.27). - Labor substitution: Household registers show growing substitution of wage workers for slaves. In Eonyang, the slave-to-wage-worker ratio declined from 1.54 (1777) to 1.08 (1825). Real farm wages tended to rise after 1801 as slave demand contracted. - Comparative context: Unlike the antebellum U.S. (where real slave prices rose in the 19th century), Korea’s real slave prices declined amid rising desertions, highlighting a distinct, desertion-driven collapse of slavery. - Social implications: Desertion into informal sectors contributed to market fragmentation, high goods and loan prices, and low social capital/trust within Korean society during the period.

Findings support the hypothesis that the 1731 regulation change increased slave desertions, raising monitoring costs and reducing slave demand, which manifested as declining real slave prices and greater use of wage labor. Because Korean slaves were indistinguishable from commoners and benefited from policy shifts (including limits on owners’ pursuit and physical punishment), desertion was relatively feasible, pushing many into informal economic niches. This migration eroded dense social networks, reduced trust, and fragmented markets, contributing to high credit costs. Econometrically, after instrumenting for slave population, desertion and the regulatory shift significantly depressed real slave prices, consistent with heightened monitoring burdens. The transition toward wage labor appears Pareto-improving relative to an increasingly costly, unstable slave system. The Korean trajectory contrasts with Atlantic slavery economies, underscoring how local institutional changes and social structures shape slavery’s evolution and demise.

The study documents an informal collapse of slavery in Chosun-era Korea driven by legal change in 1731 and ensuing slave desertions. Desertion increased monitoring costs, depressed real slave prices, and precipitated the substitution of wage labor for slave labor well before formal abolition in 1894. By linking household tallies, transaction prices, and econometric analysis, the paper shows that desertion, not merely population decline, was pivotal in shifting the labor regime and weakening Korea’s hereditary status system. Future research could expand geographic and temporal coverage of household tallies and transaction records, refine measures of monitoring costs and informal-sector participation, and explore micro-level heterogeneity (gender, age, task specialization) in desertion and labor substitution dynamics.

- Data constraints: Slave transaction records (634 cases) are dispersed across private documents; Korea lacked organized slave markets, limiting volume and standardization of price data relative to Atlantic cases. - Measurement issues: Slave population data from household tallies may contain errors and endogeneity with desertion; overall population estimates (Kwon and Shin, 1977) also have missing values and measurement error. - Proxy assumption: Monitoring costs are inferred from real slave prices; direct monitoring-cost measures are unavailable. - External validity: Evidence centers on three counties in Kyungsang province and a single large household (Daegu-Choi), which may limit generalizability across regions or social strata. - Model limitations: Despite 2SLS addressing endogeneity in slave population, other unobserved factors (e.g., regional shocks, enforcement intensity, local labor-market conditions) could influence prices and desertion.