南昌起義
After the failure of the Nanchang Uprising, Zhou left China for the Soviet Union to attend the Chinese Communist Party's (CCP) Sixth National Party Congress in Moscow, in June–July 1928. The Sixth Congress had to be held in Moscow because conditions in China were considered dangerous. KMT control was so tight that many Chinese delegates attending the Sixth Congress were forced to travel in disguise: Zhou himself was disguised as an antiquarian.