 The initiation of war may also have been brought by the desire to remove the possibility that Gojoseon would ally with the Xiongnu against the Han.Another reason may also have been the deteriorating relations between Han and Gojoseon, because Wiman Joseon had prevented trade between Han and polities such as Jinbeon (진번, 眞番).In 109 BCE, Emperor Wu launched a Han military campaign into Gojoseon.