グリゴリー・ジノヴィエフ
This congress was the Russian Communist Party (Bolsheviks)' first to take place after the death of Vladimir Lenin, and represents a transition between the Lenin and Joseph Stalin regimes. It was also the first confrontation between the Left Opposition (led by Leon Trotsky) and the "troika" (led by Stalin, Grigory Zinoviev, and Lev Kamenev).