Lenin was 47 when the Bolsheviks seized power
In late August 1918, he was shot by a member of the now banned Socialist Revolutionary Party, Fanny Kaplan (who was shot a few weeks later)
Lenin survived the assassination attempt, but his health never really recovered. He suffered a series of strokes that left him debilitated by 1923. He died in January 1924, with the question now of who could follow him
The Bolshevik Party (now Communist Party), had changed since it came to power. There was no room for debate and argument as the stresses and strains of the Civil War and Communism, and the Bolsheviks' life and death struggle for survival contributed to this. Ranks, uniforms, corporal punishment and the death penalty had been brought back into the Red Army. Violence and terror that was part of the Civil War would gradually become an accepted part of Soviet political life.
Stalin had defeated all rivals for leadership of the party by the late 1920s
He had supreme power in the Soviet Union until his death in 1953.
Every aspect of life in the Soviet Union came to be dominated by the party, including factories, collective farms, education, trade unions, sport, the arts and youth organisations that the young were forced into (known as Komsomol)
Created Five Year Plans which dictated the direction in which the economy was to take. Stalin's preference was for heavy industry
The party also maintained strict control over education and the media, where only views acceptable to the party (i.e. Stalin) were allowed
A cult of personality grew around Stalin, and his portrait was in every home, school, office and factory and statues of him in every town
Propaganda was everywhere extolling the achievements of Stalin's rule
His dictatorship relied on force and terror - such things existed before Stalin, but in the 1930s the use of terror grew enormously. For example; he adopted a secret police, called the NKVD from 1934, to become a permanent part of the regime and labour camps were established in the least hospitable parts of the country such as Siberia and the Arctic. It is estimated that millions of people died during the course of Stalin's dictatorship.