There were many reasons for the Peking (Beiyang) government’s failure.  Its fecklessness led to the organization and planning of the massive nationalist campaign in China in the 1920s. Its goal was to unify China and expel or neutralize foreign intrusion and interference.  Russia ironically played a large role. 

Through the merger of the Guomindang Nationalists and the Communists, the government in Peking was cast out.  Chiang Kai-Shek emerges during this period as a key leader.  He led the Nationalists in the Northern Expedition to establish a new government in Nanjing in 1928. Later he expelled the Communists from the new government and the Guomindang.