1924: Lenin dies.
1925: Trotsky dismissed as commissar of war.
1926: Kirov appointed Party Secretary in Leningrad. Trotsky dismissed from Politburo.
1927: Trotsky and Zinoviev dropped from Central Committee and expelled from the party.
1932: Non aggression pacts with Baltic States and France.
1933-37: The Second Five Year Plan.
1935: Assistance pact with France. Assistance pact with Czechoslovakia.