sentences:  Four Commanderies of Han
  
  The Four Commanderies of Han () were Chinese commanderies located in the north of the Korean Peninsula and part of the Liaodong Peninsula from around the end of the second century BC through the early 4th AD, for the longest lasting.The commanderies were set up to control the populace in the former Gojoseon area as far south as the Han River, with a core area at Lelang near present-day Pyongyang by Emperor Wu of the Han dynasty in early 2nd century BC after his conquest of Wiman Joseon.