Overview
The Lelang Commandery was a commandery of the Han dynasty established after it had conquered Wiman Joseon in 108 BC and lasted until Goguryeo conquered it in 313. The Lelang Commandery extended the rule of the Four Commanderies of Han as far south as the Han River in present-day South Korea. South Korean scholars have described its administrative areas as being limited to the Pyongan and Hwanghae regions, whose southern bounds lie roughly 75 miles north of the Han River.
History
Han dynasty
In 108 BC, Emperor Wu of the Han dynasty conquered the area under King Ugeo, a grandson of King Wiman. The Emperor set up Lelang, Lintun, Xuantu and Zhenfan, known as the Four Commanderies of Han in the northern Korean peninsula and Liaodong peninsula. The Book of Han records Lelang belonged to Youzhou, located in northwestern Gojoseon consisted of 25 prefectures, 62,812 houses, and the population was 406,748. Its capital, then the prefecture of Joseon (朝鮮縣, 조선현), was located at modern P'yŏngyang. (Rakrang 樂浪/락랑, a district in central P'yŏngyang today, is named after Lelang.)
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