After the Bolshevik government withdrew from World War I, the Allied Powers openly backed the anti-communist White forces in Russia. Allied intervention in the Russian Civil War consisted of a series of multi-national military expeditions in 1918. The stated goals were to help the Czechoslovak Legion, to secure supplies of munitions and armaments in Russian ports, and to re-establish the Eastern Front. Overthrow of the new Bolshevik regime was an additional, covert motivation. Allied efforts were hampered by divided objectives, war-weariness from the overall global conflict, and a lack of domestic support. These factors, together with the evacuation of the Czechoslovak Legion, compelled the Allied Powers to withdraw from North Russia and Siberia in 1920, though Japanese forces occupied parts of Siberia until 1922 and the northern half of Sakhalin until 1925.