直皖戰爭
During the Russian Civil War, Japan supported White movements in northeast Asia such as Grigory Mikhaylovich Semyonov's White movement in Transbaikal and the Chinese Beiyang government's Occupation of Mongolia during the primacy of the Anhui clique. However, the movements failed and the White Army fled to Manchuria. In 1920, the Zhili–Anhui War began and the Anhui clique was beaten; by 1921, the Red Army had control of outer Mongolia.