| From the perspective of the interaction of domestic and foreign politics, the paper studies the relationship of Wu Peifu and the Soviet Union between 1925 and 1927. The paper analyzes the reason that Wu fought against the Soviet Union, discusses the multifaceted nature of Wu's personality, interprets the evolution of China's history on the eve of the "Northern Expedition" .This paper is divided into the following three parts.The first part discusses the process that the Soviet Union requested the cooperation with Wu before and after the 1926, and Wu asked for the British's help. To implement China's strategic plan and promote cooperation between Wu and Feng, the Soviet Union actively contacted with Wu and committed to provide a large number of assistance. The result was that Wu refused to the request of Soviet cooperation, and united Chang Tso-lin against Feng Yuxiang. Wu asked for the British's help when British was against the Soviet Union, but Wu was rejected by the British.The second part discusses the process of confrontation between Wu and the Soviet Union and analyzes the reason of Wu's failure. Under Wu's rule, the politics was dark and unfair, and the people lived in difficulty, which aroused strong dissatisfaction of public opinion. Feng and the KMT received substantial assistance from the Soviet , while Wu was lack of foreign aid, which was an important reason for Wu's failure.The third part discusses the reason why Wu refused the co-operation with the Soviet Union. First, the intellectuals who were against the Soviet influenced Wu's attitude. Secondly, Soviet policy toward China hurt Wu's national sentiments. At last, because of Wu's political ethics, he couldn't forgive Feng Yuxiang's betray , and refused to cooperate with Feng. This paper argues that Wu's political ethics is the important reason for Wu to fight against the Soviet Union and asked for help from British. Wu's lack of foreign aid had an important influence on his failure ,When the foreign forces deeply affected the domestic politics. |