The Red Army was the military force of the Soviet Union, established after the Bolshevik Revolution in 1917. It played a crucial role in the Russian Civil War, fighting for the Bolshevik government against various anti-Bolshevik factions, known as the White Army. The Red Army's formation marked the beginning of a new era in Russian military history, reflecting the broader political and social upheavals resulting from the Russian Revolution and its aftermath.