Compilation of the Dongguk tonggam

Under King Seongjong, Seo Geo-jeong and others published the Dongguk tonggam, a chronological general history from Gojoseon to the end of Goryeo.

Continuing work begun under Sejo, Seo Geo-jeong and others completed it in 56 volumes in 1485, the 16th year of Seongjong. Dangun, Gija and Wiman Joseon and the Three Han come first as an "outer record"; the Three Kingdoms, Unified Silla and Goryeo follow by date. No one of the Three Kingdoms is treated as the legitimate line.

Compiled as the Sarim were entering central government, it carries historians’ comments based on Neo-Confucian moral principles. It was the first official general history to cover the whole of Korea’s past.