Fall of Gojoseon
Also called: Four Commanderies of Han
Emperor Wu of Han captured Wanggeom-seong and destroyed Gojoseon, setting up four commanderies including Lelang.

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When Gojoseon blocked direct trade between Han and the southern state of Jin, Emperor Wu attacked by land and sea in 109 BCE. King Ugeo held Wanggeom-seong for almost a year until a split among his nobles led to his murder, and the city fell the next year.
Han set up the Lelang, Zhenfan, Lintun and Xuantu commanderies — the Han commanderies, often called the Four Commanderies (Hansagun); Lelang lasted until Goguryeo expelled it in 313. After the commanderies arrived the laws reportedly grew to more than sixty articles and customs grew harsher. Three surviving articles of Gojoseon’s Eight-Article Law (beomgeum paljo) — death for murder, grain for injury, enslavement for theft — show its society.