Allied invasion of Russia, the military intervention of World War I allies, Great Britain, France, USA, Italy, Romania, Japan, etc. undertaken during the Civil War in Russia. The main goals of the allied intervention consisted in the preservation of the Eastern Front, protection of property and citizens of the allied states on the territory of Russia, exploitation of resources, and removal of material assets from occupied territories.
As the Bolsheviks came to power in October 1917, they called for an immediate end to the war and launched negotiations with the Central Powers. This step was strongly resented by the allies. At the end of 1917, they decided to support the forces that did not recognize Soviet power. On March 3, 1918, Soviet Russia and the Central Powers concluded the Peace Treaty of Brest-Litovsk. The Allies declared non-recognition of this separate treaty.
The relations between Soviet Russia and Entente countries aggravated in May 1918, when Germany demanded strict compliance with the terms of the Peace Treaty of Brest-Litovsk, including the internment of the allies' servicemen on its territory. In the second half of May 1918, this (along with some other factors) provoked anti-Soviet actions of the Czechoslovak Legion (which had been subordinate to the French command since the end of 1917). Thus, large-scale hostilities within the framework of the Civil War in Russia began. Subsequently, the Legion participated in hostilities against the Reds in the Volga region, the Urals, and Siberia until the beginning of 1920.
March 6, 1918, saw British troops land in Murmansk, as had been agreed with the local Soviet (and approved by the Bolshevik leadership). They were to assist in the face of the threat of an offensive by German and Finnish troops. On June 30, Murmansk Regional Council decided against complying with the requirements of the Council of People’s Commissars of the Russian SFSR on the removal of the Entente troops. So, the allies' military and economic assistance were accepted. This marked the beginning of anti-Bolshevik operations of the Entente troops on the Kola Peninsula. On August 2, 1918, a British landing party landed in Arkhangelsk, which enabled the victory of the anti-Soviet coup and the formation of the Northern Region. Until the beginning of 1919, the main anti-Bolshevik military force in northern Russia had been the Allied Expeditionary Force, which consisted of British troops (including Australian and Canadian units), French, American, and other troops. In June – September 1919, the Allies were evacuated from the region.
On April 5, 1918, the Japanese and British troops landed in Vladivostok, and the invasion of the Far East began. In the summer of 1918, Japanese troops advanced into Primorye and Transbaikalia, where they supported Ataman Grigory Semyonov. Japanese forces left Transbaikalia in the summer of 1920 and evacuated from Vladivostok in the autumn of 1922. In 1920–1925, Japan occupied Northern Sakhalin. Besides, American and Italian forces were present in Siberia.
In April 1918, Romania, which had also been Russia’s ally in World War I, annexed the Moldavian Democratic Republic, formed at the beginning of the year on the territory of the former Bessarabian governorate. Soviet Russia did not recognize these actions and regarded them as an occupation.
After the defeat of Germany, Entente provided support to Poland, Latvia, Lithuania, and Estonia, in the struggle for establishing their sovereignty over the Russian Empire’s former territories. All these states clashed with local pro-Bolshevik forces and the Red Army units.
After the victory over the Central Powers at the end of 1918, the allied forces entered the Black Sea region. British and French troops landed in Sevastopol, the French and Greeks occupied Kherson, Odessa, and the nearby area in southern Ukraine. In April 1919, the Entente troops were evacuated from Odessa and Crimea.
From the end of 1918, British troops were deployed in Transcaucasia as well. They occupied the key cities of the region: Baku, Erivan (Erevan), Batum (Batumi), etc., as well as the Trans-Caspian Region, where, under their pressure, the Trans-Caspian provisional government was dissolved. The British military left the main part of the Transcaucasia and the Trans-Caspian region in the second half of 1919. In the summer of 1920, they left Batum.
By the autumn of 1919, Entente countries (except Japan in the Far East) had withdrawn from military support for the White movement. However, they continued to supply weapons, lend funds, etc. The invasion of allied states caused significant damage to the Whites’ political reputation.