In 109 BC, Emperor Wu sent General Guo Chang () south to Yunnan, establishing the Yizhou commandery. The commandery seat was at Dianchi county (present day Jinning). To expand the burgeoning trade with Burma and India, Emperor Wu also sent Tang Meng () to maintain and expand the Five Foot Way, renaming it "Southwest Barbarian Circuit" (). By this time, agricultural technology in Yunnan had markedly improved. The local people used bronze tools, plows and kept a variety of livestock, including cattle, horses, sheep, goats, pigs and dogs. They lived in tribal congregations, sometimes led by exile Chinese.