张胜 / Zhang Sheng (Western Han envoy)
张胜 / Zhang Sheng enters the wiki through Hanji 191 as the 卢绾 envoy sent to 匈奴 during the 陈豨之乱. He first appears as Yan’s official channel to the steppe while Lu Wan is nominally attacking 陈豨 from the northeast.
In Xiongnu territory, 臧衍 persuades Zhang Sheng that quick Han success against Chen Xi may make 燕国 the next target of 刘邦’s different-surname king rollback. Zhang Sheng accepts the argument and secretly asks Xiongnu to help Chen Xi resist Yan pressure.
Lu Wan initially denounces Zhang Sheng and asks to punish his family, but Zhang Sheng returns and explains the argument. Lu Wan then preserves Zhang Sheng’s family by substituting another family for punishment and secretly sends Zhang Sheng back to Xiongnu as an envoy. Later Xiongnu surrenderers reveal that Zhang Sheng’s family was not killed, making him key evidence in Liu Bang’s conclusion that Lu Wan has rebelled.