Sino-Soviet Non-Aggression Pact

The Sino-Soviet Non-Aggression Pact (traditional Chinese: 中蘇互不侵犯條約; simplified Chinese: 中苏互不侵犯条约; pinyin: Zhōng-sū hù bù qīnfàn tiáoyuē) was signed in Nanjing on August 21, 1937, between the Republic of China and the Soviet Union during the Second Sino-Japanese War. It went into effect on the day it was signed. It was registered in League of Nations Treaty Series on September 8, 1937.

At first the treaty led to improving relations between the Kuomintang, Chiang Kai-shek's government and the USSR. Following the signing of the pact, the Soviet Union began sending aircraft to the Chinese national government in Operation Zet, as well as economic aid to help stave off Japanese occupation. Chiang hoped this was a precursor to Soviet intervention into the war, however as time passed he soon realized that the USSR was constricted in what aid it could actually provide, due to not wanting to upset the tacit alliance with Britain, France, and later the United States, who favored China in the war but, would back Japan against the USSR in order to weaken both.

The treaty also allowed the USSR to focus its attention more on the Western border where Nazi Germany was building up for what appeared to be war with the USSR especially after the Soviet-Japanese Neutrality Pact was signed. The pact contributed to the worsening relationship between China and Nazi Germany, which culminated in the end of German military assistance in China.

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