Many folks believe that after the Russian Revolution in 1917 that the Communists immediately took power and the rest is history. In fact, there was a brutal civil war between the Red Army and White Army. The fighting over three years killed at least three million Russians.
Even foreign powers got involved in the Russian Civil War with the British Empire, Japan and Czechoslovakia got involved on the side of the White Russians. You can read about this bloodly combat here.
Below is very rare footage from the Russian Civil War.