This chapter analyzes the main processes of the civil war in the territory of the former Russian Empire. The civil war was a complex of interrelated wars: a fleeting civil war associated with the establishment of Soviet power (the “triumphal march of Soviet Power” on November 8, 1917, to February 1918), local armed clashes in the spring of 1918, a large-scale civil war (May 1918 to November 1920), the uprisings against the communist regime (late 1920 to early 1922), the end of the civil war in the Far East (1920–1922), the foreign intervention of 1918–1922, and a number of wars related to the formation of national states and internal conflicts within them (“wars of independence” and civil wars in Finland, the Baltic States, Ukraine, Transcaucasia, Central Asia, and the Soviet-Polish war of 1919–1920). The author focuses on the causes of the civil war, the mobilization of enemy forces, the role of the Reds, the Whites, the rebels and the national forces, the use of terror and the character of violence, and the fate of war participants.