He attended the Yalta Conference with Stalin , who introduced him to U.S. President Franklin D. Roosevelt as " our Himmler " . After the war , he organized the Communist takeover of the state institutions in Central Europe and Eastern Europe and political repressions in these countries . Beria 's uncompromising ruthlessness in his duties and skill at producing results culminated in his success in overseeing the Soviet atomic bomb project . Stalin gave it absolute priority and the project was completed in under five years , having been accelerated by Soviet espionage against the West
Yalta Conference
Yalta Conference
Lavrentiy Beria