The conditions that led to the Russian Civil War in 1918-1920 were
1. The coming to power by the Bolsheviks led by Lenin after overthrowing the Provisional government of Kerensky.
2. The ideological clash between the Bolsheviks who wanted to establish a communist state and alternative ideologies like monarchism, economic capitalism and alternative forms of socialism.
3. The formation of the Red Army by the Bolsheviks which enabled them to engage in war.
4. The intervention of the foreign powers like former allies of the Russian Tsarist government against the Bolsheviks.