structural:summarization
Government by in-law families

After the death of King Jeongjo, the Joseon faced difficult external and internal problems. Internally, the foundation of national law and order weakened as a result of "Sedo Politics" (in-law government) by royal in-laws.

The young Sunjo succeeded his father, King Jeongjo, in 1800. With Jeongjo's death the Noron seized power with the regency of Queen Dowager Jeongsun, whose family had strong ties to the faction, and initiated a persecution of Catholics. However, after the retirement and death of the Queen Dowager, the Norons were gradually ousted, while the Andong Kim clan of Kim Jo-sun, the father of the Queen Sunwon, gained power. Gradually the Andong Kims came to dominate the court.

With the domination of the Andong Kims, the era of Sedo Politics began. The formidable in-law lineage monopolized the vital positions in government, holding sway over the political scene, and intervening in the succession of the throne. These kings had no monarchic authority and could not rule over the government. The other aristocratic families, overwhelmed by the power exercised by the royal in-laws, could not speak out. As the power was concentrated in the hands of the royal in-law lineage, there was disorder in the governing process, and corruption became rampant. Large sums were offered in bribes to the powerful lineages to obtain positions with nominally high rank. Even the low-ranking posts were bought and sold. This period, which spanned 60 years, saw the manifestation of both severe poverty among the Korean population and ceaseless rebellions in various parts of the country.

Externally, Joseon became increasingly isolationist. Its rulers sought to limit contact with foreign countries.