The new government, led by Lenin, made peace with the Germans and undertook a bloody, three-year civil war, in which Stalin commanded on several fronts. The real hero of the conflict, however, was Leon Trotsky, a former Menshevik who organized the Red Army and guided the Bolsheviks to victory.
After the war, the Bolsheviks renamed themselves the Communist Party, and declared Russia the Union of Soviet Socialist Republics. Stalin was elected General Secretary of the Party in 1922, and although he quickly began to increase his personal power, no one realized how dangerous he was at this time. As he neared a 1924 death, Lenin began to grow wary of his former protégé, and wrote a Testament warning against Stalin's influence. But the other members of the Politburo, Lenin's circle of advisers, ignored the Testament and allowed Stalin to remain in a position of power. At this point, Stalin began his rise to dominance by destroying his rival Trotsky, expelling him from the party in 1927 and exiling him from the Soviet Union in 1929. Meanwhile, he brilliantly played the Politburo's factions off one another, first allying with Nikolai Bukharin and his "Rightists" to destroy the "Leftists," and then, when his position was secure, turning on Bukharin and destroying his power. !.
By 1930, he stood alone atop the Party and the Soviet Union.
Once in power, Stalin began a drive to industrialize and modernize the Soviet Union, with a Five-Year Plan (1927-32) based on Marxist principles championing government control of the economy. Central to his program was the collectivization of agriculture, in which the government would redistribute the land by taking over the estates of the "kulaks", the wealthiest peasants. But the kulaks were essentially a figment of Marxist propaganda (there existed no real difference between these "wealthiest" peasants and all other peasants), and collectivization reaped disaster--the government persecuted and killed the peasantry, famine swept the country, and as many as ten million may have died.