After the Bolsheviks' seizure of power in Petrograd, the All-Siberian Extraordinary Congress of Delegates from Public Organizations, was convened in Tomsk on December 7, 1917. The SR-dominated assembly refused to recognize Soviet authority or its decrees, and during its last session on December 15 called for the convocation of an “all-socialist” Siberian Regional Duma and appointed a Provisional Siberian Council, answerable to the Duma, that would “act as a government.” The opening of the Duma was set for January 8, 1918.
As it happened, the Duma could not open on the date the congress had set for it for lack of a quorum requiring that a minimum of one-third of the delegates, or ninety-three, be present. Many of the delegates had already been arrested by local Bolshevik authorities; others had not been able to reach Tomsk.
When three weeks later, on the night of January 28–29, some forty delegates finally succeeded in meeting, they expeditiously elected a government known as the Provisional Government of Autonomous Siberia (PGAS), under the chairmanship of a young Socialist-Revolutionary Pyotr Derber. Another member of SR Party - colonel Arkady Krakovetsky - became a Minister of War, his task was to organize an anti-Bolshevik rebellion in Siberia. Krakovetsky appointed two representatives: stabskapitän Frizel in West-Siberian Military District, and praporshchik Kalashnikov (both - members of SR Party). But there also were many independent underground military organisation with experienced officers as members. Hence SR-members quickly became driven away in underground organizations. In Western Siberia the main person became colonel Aleksey Grishin-Almazov, in Eastern Siberia - colonel A.Ellerts-Usov. To coordinate the efforts they created the Central Staff in Novonikolaevsk, Grishin-Almazov became the chief of this Staff.
Creation of the Army 
The Revolt of Czechoslovak Legion at May, 1918, radically changed the situation in Siberia. At May, 25, Czechoslovaks captured Mariinsk, the next day - Chelyabinsk and Novonikolaevsk. On May, 28, A.Grishin-Almazov came to Novonikolaevsk and proclaimed himself as the commander of all troops in the Western Siberian Military District.
At that time most members of PGAS (including Derber and Krakovetsky) were in Vladivostok, hence it was necessary to create a structure of government without them. On May 30, a meeting took place in Novonikolaevsk, the so-called "Council of representatives of PGAS", which organized the provisional Western Siberian Commissariat.
On June 12, 1918, Grishin-Almazov ordered the renaming of the Staff of the Western Siberian Military District (located in Omsk) into the Staff of the Western Siberian Independent Army. Members of Staff were the officers of old Russian Imperial Army, hence there was no longer any influence of the deposed Socialist-Revolutionary Party.
On June 30, 1918, the Western Siberian Commissariat transferred its power to the Provisional Siberian Government (PSG), headed by Petr Vologodskii. Grishin-Almazov was appointed as Minister of War, but he decided not to create a Ministry of War, he preferred to use the structure of the Staff of the Western Siberian Independent Army as a Ministry of War.
Structure of the Army 
On June, 13, 1918 all troops under the command of Grichin-ALmazov were concentrated into two corps: the Steppe Siberian Corps (with its headquarter in Omsk, commander - colonel Pavel Ivanov-Rinov) and the Middle Siberian Corps (with its headquarter in Novonikolaevsk, commander - subcolonel Anatoly Pepelyayev). On July, 11, the Ural Corps (with its headquarter in Chelyabinsk, commander - Mikhail Khanzhin) was formed and organized. On August, 1918, Siberian Army had three corps of twenty-three 4-regimental divisions each (23,147 infantrymen, 14,888 cavalrymen and 22,224 unarmed volunteers).
At first, the Siberian Army was a volunteer army, but there became obvious that for the creation of a real army it was necessary to organize a program of conscription. The conscription began on August 25, 1918, and by October 1918, the Siberian Army had 10,754 officers and 173,843 soldiers.
It was obvious that by the summer of 1918 the main military force in the eastern part of Russia was the Czechoslovak Legion. During the meeting in Chelyabinsk, which took place on July 13, 1918, it was decided that before the appointment of the Chief of all allied forced in Russia the Siberian troops on the front line would be placed under the command of the head of Czechoslovak Legion, general-major Vladimir Shokorov (he was an officer in Russian Army during the First World War). At the end of summer, when the Siberian Army became more powerful, and Shokorov was replaced by Jan Syrový as a head of Czechoslovak Legion, tensions began to develop between the Russians and Czechoslovaks.
On September 1918, during the State Conference in Ufa it was decided that the Provisional Government of Autonomous Siberia and the Committee of Members of the Constituent Assembly should form a united Provisional All-Russian Government with Nikolai Avksentiev as its head. General-lieutenant Vasiliy Boldyrev replaced Jan Syrový as a head of all allied forces in Russia. Ivanov-Rinov from the Siberian Army became a new Minister of War and a new head of Siberian Army. Boldyrev reorganized all anti-Bolshevik forces in Eastern Russia into three Fronts: Western, South-Western and Siberian. Ivanov-Rinov became commander-in-chief of the entire Siberian Front.
After a military coup d'état in November 1918, when Admiral Alexander Kolchak proclaimed himself the Supreme Ruler of Russia, Boldyrev was forced to emigrate. In December 1918, Kolchak dissolved the old Siberian Army, and created a new one on the base of the Ekaterinburg Group (included the 1st and 3d Corps of the Siberian Army and some other troops) with Radola Gajda as its commander. The Siberian Front was reorganised into the 2nd Steppe Siberian Corps with general Brzhezovsky as its commander.
In July 1919, the Siberian Army was divided into the 1st and 2nd Armies. Together with the 3d Army they formed an Eastern Front of the White Movement. After several crushing defeats at the hands of the resurgent Red Army, the Eastern front largely collapsed and dissolved by November 1919. The last troops of the Siberian Army retreated to the Transbaikal Region and were incorporated into the Far East Army.
- Н.Е.Какурин, И.И.Вацетис "Гражданская война. 1918-1921" (N.E.Kakurin, I.I.Vacietis "Civil War. 1918-1921") - Sankt-Peterburg, "Polygon" Publishing House, 2002. ISBN 5-89173-150-9